Human in the loop checkpoints. A practical lesson in model governance and validation for banking and payments practitioners.
How to study this topic
Human in the loop checkpoints are the points where an authorised banking person must review model output, evidence, limitations and customer or regulatory impact before the bank allows the process to continue. Study this as a banking governance chapter. The important question is not whether AI can produce a score, explanation or document pack. The important question is whether the bank can prove the model is suitable, lawful, monitored, limited and accountable for human oversight, decision accountability, high-impact review, exception handling, customer protection and operational control.
The topic belongs to human oversight and banking AI decision checkpoints. Keep the focus on credit, compliance, model-risk governance, fair lending, customer outcome, validation evidence and approval control. Do not drift into generic AI productivity language. In banking, the model output matters only when the control context around it is strong enough.
A strong learner should be able to explain this topic to a credit-risk manager, fair lending specialist, compliance analyst, model validator, product owner, developer, tester, auditor and governance committee member. Each person should understand what evidence is needed, what the model can do, what it cannot prove and where human accountability remains.
Plain language meaning
In plain language, human in the loop checkpoints is about preventing AI from being treated as trusted banking evidence before the bank has tested the model, checked the law, reviewed the customer impact and agreed the approval boundary. A model can be technically impressive and still be unsuitable for a regulated credit or compliance use.
The practical discipline is to separate prediction, explanation, compliance evidence and final action. Prediction estimates an outcome. Explanation describes model drivers. Compliance evidence proves the bank followed the right control process. Final action affects a customer, report, control, case or policy position. Mixing those four layers is where many model-governance failures begin.
A good bank does not approve AI because it sounds modern. It approves a controlled use of a specific model for a specific population, purpose, product, jurisdiction and decision boundary. That approval should be visible in the model inventory, validation pack, committee record and monitoring process.
Where it sits in the bank
This topic normally sits across credit risk, compliance, fair lending, legal, model risk management, product, data, technology, operations and internal audit. The exact operating model differs by bank, but ownership must not be vague. Someone must own the model, someone must validate it, someone must approve use and someone must monitor the outcome.
The population in scope is credit applicants, declined customers, manual referrals, vulnerable customers, high-risk AML cases, sanctions reviews, model overrides, complaint cases, regulatory-impact decisions and operational exceptions. Testing must reflect the population actually affected by the model. Clean demonstration examples are not enough. Banking populations include missing data, thin files, local policy exceptions, manual overrides, legacy records, vulnerable customers, new products, rejected applicants and changing economic conditions.
The output may support application scoring, limit setting, pricing, referral, adverse action notices, compliance review, model approval, documentation review, audit evidence or regulatory response. The risk level changes when the same model moves from research to decision support, then from decision support to automated action.
Evidence and source material
Relevant evidence includes model score, recommendation, reason code, source evidence, policy rule, case facts, customer-impact flag, materiality level, review checklist, reviewer identity, decision note, override reason, escalation record, and final action. Evidence must be current, traceable and fit for the question being asked. A policy document, model metric, explanation output, validation report or approval note is useful only when the bank can show source, version, owner, date, limitation and approved use.
For credit and fair lending topics, evidence also needs customer-outcome context. A model that performs well at portfolio level can still create unacceptable outcomes for a subgroup, a product segment, a pricing path or a manual referral population. Aggregate accuracy does not remove the need for segment-level challenge.
For model approval topics, evidence must connect the business purpose to the technical method. A validator should be able to see why the model was built, what data it uses, how it was tested, what limitations remain, what risks were accepted and how those risks will be monitored after release.
Control expectations
Controls should include human-review trigger, role-based authority, four-eyes control, evidence display, override capture, escalation rule, materiality threshold, review quality sampling, training control, conflict-of-interest control, audit log, and feedback loop. These controls make the difference between a useful model and an uncontrolled model. The bank should know what must be documented before use, what must be validated independently, what must be approved by governance and what must be monitored in production.
Control design should be proportionate to materiality. A low-risk internal research tool does not need the same approval pack as a model that affects credit access, pricing, limits, regulatory reporting or customer communication. But once the model can influence a material banking outcome, casual governance is not enough.
Controls should also define the response when something is wrong. That may mean restricting use, forcing manual review, changing thresholds, updating reason codes, remediating documentation, retraining users, opening an issue, notifying a committee or stopping the model until the gap is closed.
How AI and ML can be adopted
Useful AI adoption includes preparing review packs, highlighting policy conflicts, flagging missing evidence, ranking cases by materiality, suggesting questions for review, and tracking override patterns. These are support uses first. AI can help find weak documentation, monitor patterns, summarise validation packs, detect proxy risk, compare outcomes and prepare governance material. It should not quietly replace the bank's legal, compliance, validation or approval judgement.
A sensible adoption path starts with controlled analysis and documentation support, then moves into validated decision support, then into restricted automation only when governance, monitoring, fallback and accountability are mature. The higher the customer or regulatory impact, the stronger the approval boundary must be.
The bank should write the model's role in operational language: score, explain, classify, recommend, refer, approve, decline, price, notify, document, monitor or escalate. Each verb carries a different control burden. If the bank cannot name the verb precisely, it cannot govern the use precisely.
Validation and challenge
Validation should review concept, data, methodology, assumptions, implementation, outcome quality, limitations, fairness, explainability, operational use and monitoring design. For banking AI, validation is not a final signature at the end. It is a structured challenge to whether the model is fit for the stated purpose.
Effective challenge means the validator can question the developer, the business owner, the data source, the training sample, the feature logic, the testing design, the reason-code mapping, the customer impact and the proposed monitoring thresholds. Challenge should be documented, answered and closed with evidence.
A model may pass technical accuracy tests and still need restrictions. It may be acceptable for analyst prioritisation but not for automatic decline. It may be acceptable for one product but not another. It may be acceptable in one jurisdiction but not another. Validation should make those boundaries visible.
Customer, compliance and conduct impact
The direct wrong outcome is human review becomes a rubber stamp because the reviewer cannot see evidence, cannot challenge the model, lacks authority or is pressured to accept the AI output. That is why this topic should be studied as customer-impact control, not only model governance theory. Credit AI can affect access, price, limit, explanation, complaint handling and trust. Compliance AI can affect evidence, escalation and regulatory position.
A bank must ask who is affected when the model is wrong. Is a sustainable applicant declined? Is an unaffordable customer approved? Is a protected group disadvantaged? Is a reason code inaccurate? Is a reviewer over-trusting the explanation? Is a governance committee approving a model without seeing a key limitation?
Conduct risk appears when the model creates pressure, exclusion, opacity, delay, poor explanation or weak remediation. The bank should treat those outcomes as control issues, not as cosmetic issues in the user interface or documentation wording.
Diagram walkthrough
The diagram follows five control steps: Model output, Review trigger, Human evidence check, Decision or escalation, and Feedback loop. Read it left to right. It starts with the model or regulatory use case, moves through testing and governance, and ends with accountable use and retained evidence.
Each box is a bank control point. The implementation should name the owner, input, rule, evidence, review point and limitation at every step. If one box cannot be explained clearly, the model is not ready for high-trust banking use.
Bank-ready checklist
Before using this topic in production, ask whether the model purpose is clear, the legal classification is understood, the population is defined, the data is governed, the validation is independent, the customer impact is tested and the approval boundary is documented.
Then ask whether the monitoring thresholds, override process, adverse action reason logic, issue management, change control, audit pack and retirement criteria are in place. Banking AI governance is only strong when the bank knows what happens after approval, not just before approval.
If the answers are strong, the model can support banking work with discipline. If the answers are weak, the model may still produce a result, but the bank should not treat that result as controlled evidence for customer, regulatory or financial impact.
Source anchors for accurate study
Federal Reserve SR 26-2, dated 17 April 2026, supersedes SR 11-7 and SR 21-8 and attaches revised model-risk guidance for banking organisations.
The 2026 interagency model-risk guidance focuses on model development and use, validation and monitoring, governance and controls, and vendor or third-party model products.
The revised model-risk guidance says model risk depends on inherent risk, exposure, purpose and use, and that practices should be tailored to the bank's risk profile and model usage.
The EU AI Act treats AI systems used to evaluate the creditworthiness of natural persons or establish a credit score as high-risk, except where the system is used for financial fraud detection.
The EU AI Act high-risk framework includes controls around risk management, data governance, technical documentation, record keeping, transparency to deployers, human oversight, accuracy, robustness and cybersecurity.
ECOA and Regulation B require creditors to provide specific and accurate reasons for adverse action; using a complex algorithm does not remove that obligation.
U.S. Regulation B, 12 CFR 1002.9, requires specific principal reasons for adverse action in covered credit decisions, including when a creditor uses an AI model. CFPB Circular 2022-03 was withdrawn on 12 May 2025; do not cite it as current guidance. Primary sources: https://www.consumerfinance.gov/rules-policy/regulations/1002/9 and https://www.consumerfinance.gov/compliance/guidance/withdrawn-guidance/.
Federal Reserve public remarks on AI in the financial system emphasise that AI is not exempt from existing laws and risk-management expectations, including fair lending, privacy, cybersecurity, third-party risk and model risk.
NIST AI RMF describes trustworthy AI through characteristics including valid and reliable, safe, secure and resilient, accountable and transparent, explainable and interpretable, privacy-enhanced, and fair with harmful bias managed.
Banking practice note: legal classification
For human in the loop checkpoints, legal classification is not optional detail. It decides whether the bank can explain the model, defend the use and protect the customer. A model may be fast and accurate in a narrow test, but banking approval depends on whether the result is suitable for human oversight, decision accountability, high-impact review, exception handling, customer protection and operational control.
The practical test is to trace one item from model score through human-review trigger and into the business use. If the team cannot show that path without guesswork, the model pack is not mature enough for serious banking reliance.
AI adoption should strengthen governance here. It should make weak evidence easier to see, proxy risk easier to challenge, documentation gaps easier to find and unstable outcomes easier to monitor. It should not become a way to hide uncertainty behind dashboards, explanations or committee slides.
A good implementation records model owner, model version, source data, feature list, intended use, population, limitation, validation result, approval condition, user action, override decision, monitoring result and issue history. That record is what makes the topic useful to risk, compliance, technology, audit and business owners.
Banking practice note: model purpose
For human in the loop checkpoints, model purpose is not optional detail. It decides whether the bank can explain the model, defend the use and protect the customer. A model may be fast and accurate in a narrow test, but banking approval depends on whether the result is suitable for human oversight, decision accountability, high-impact review, exception handling, customer protection and operational control.
The practical test is to trace one item from recommendation through role-based authority and into the business use. If the team cannot show that path without guesswork, the model pack is not mature enough for serious banking reliance.
Banking practice note: customer population
For human in the loop checkpoints, customer population is not optional detail. It decides whether the bank can explain the model, defend the use and protect the customer. A model may be fast and accurate in a narrow test, but banking approval depends on whether the result is suitable for human oversight, decision accountability, high-impact review, exception handling, customer protection and operational control.
The practical test is to trace one item from reason code through four-eyes control and into the business use. If the team cannot show that path without guesswork, the model pack is not mature enough for serious banking reliance.
Banking practice note: source authority
For human in the loop checkpoints, source authority is not optional detail. It decides whether the bank can explain the model, defend the use and protect the customer. A model may be fast and accurate in a narrow test, but banking approval depends on whether the result is suitable for human oversight, decision accountability, high-impact review, exception handling, customer protection and operational control.
The practical test is to trace one item from source evidence through evidence display and into the business use. If the team cannot show that path without guesswork, the model pack is not mature enough for serious banking reliance.
Banking practice note: training data
For human in the loop checkpoints, training data is not optional detail. It decides whether the bank can explain the model, defend the use and protect the customer. A model may be fast and accurate in a narrow test, but banking approval depends on whether the result is suitable for human oversight, decision accountability, high-impact review, exception handling, customer protection and operational control.
The practical test is to trace one item from policy rule through override capture and into the business use. If the team cannot show that path without guesswork, the model pack is not mature enough for serious banking reliance.
Banking practice note: feature governance
For human in the loop checkpoints, feature governance is not optional detail. It decides whether the bank can explain the model, defend the use and protect the customer. A model may be fast and accurate in a narrow test, but banking approval depends on whether the result is suitable for human oversight, decision accountability, high-impact review, exception handling, customer protection and operational control.
The practical test is to trace one item from case facts through escalation rule and into the business use. If the team cannot show that path without guesswork, the model pack is not mature enough for serious banking reliance.
Banking practice note: protected-class testing
For human in the loop checkpoints, protected-class testing is not optional detail. It decides whether the bank can explain the model, defend the use and protect the customer. A model may be fast and accurate in a narrow test, but banking approval depends on whether the result is suitable for human oversight, decision accountability, high-impact review, exception handling, customer protection and operational control.
The practical test is to trace one item from customer-impact flag through materiality threshold and into the business use. If the team cannot show that path without guesswork, the model pack is not mature enough for serious banking reliance.
Banking practice note: proxy-variable review
For human in the loop checkpoints, proxy-variable review is not optional detail. It decides whether the bank can explain the model, defend the use and protect the customer. A model may be fast and accurate in a narrow test, but banking approval depends on whether the result is suitable for human oversight, decision accountability, high-impact review, exception handling, customer protection and operational control.
The practical test is to trace one item from materiality level through review quality sampling and into the business use. If the team cannot show that path without guesswork, the model pack is not mature enough for serious banking reliance.
Banking practice note: adverse action reasons
For human in the loop checkpoints, adverse action reasons is not optional detail. It decides whether the bank can explain the model, defend the use and protect the customer. A model may be fast and accurate in a narrow test, but banking approval depends on whether the result is suitable for human oversight, decision accountability, high-impact review, exception handling, customer protection and operational control.
The practical test is to trace one item from review checklist through training control and into the business use. If the team cannot show that path without guesswork, the model pack is not mature enough for serious banking reliance.
Banking practice note: reason-code mapping
For human in the loop checkpoints, reason-code mapping is not optional detail. It decides whether the bank can explain the model, defend the use and protect the customer. A model may be fast and accurate in a narrow test, but banking approval depends on whether the result is suitable for human oversight, decision accountability, high-impact review, exception handling, customer protection and operational control.
The practical test is to trace one item from reviewer identity through conflict-of-interest control and into the business use. If the team cannot show that path without guesswork, the model pack is not mature enough for serious banking reliance.
Banking practice note: explainability limits
For human in the loop checkpoints, explainability limits is not optional detail. It decides whether the bank can explain the model, defend the use and protect the customer. A model may be fast and accurate in a narrow test, but banking approval depends on whether the result is suitable for human oversight, decision accountability, high-impact review, exception handling, customer protection and operational control.
The practical test is to trace one item from decision note through audit log and into the business use. If the team cannot show that path without guesswork, the model pack is not mature enough for serious banking reliance.
Banking practice note: independent validation
For human in the loop checkpoints, independent validation is not optional detail. It decides whether the bank can explain the model, defend the use and protect the customer. A model may be fast and accurate in a narrow test, but banking approval depends on whether the result is suitable for human oversight, decision accountability, high-impact review, exception handling, customer protection and operational control.
The practical test is to trace one item from override reason through feedback loop and into the business use. If the team cannot show that path without guesswork, the model pack is not mature enough for serious banking reliance.
Banking practice note: effective challenge
For human in the loop checkpoints, effective challenge is not optional detail. It decides whether the bank can explain the model, defend the use and protect the customer. A model may be fast and accurate in a narrow test, but banking approval depends on whether the result is suitable for human oversight, decision accountability, high-impact review, exception handling, customer protection and operational control.
The practical test is to trace one item from escalation record through human-review trigger and into the business use. If the team cannot show that path without guesswork, the model pack is not mature enough for serious banking reliance.
Banking practice note: approval committee
For human in the loop checkpoints, approval committee is not optional detail. It decides whether the bank can explain the model, defend the use and protect the customer. A model may be fast and accurate in a narrow test, but banking approval depends on whether the result is suitable for human oversight, decision accountability, high-impact review, exception handling, customer protection and operational control.
The practical test is to trace one item from final action through role-based authority and into the business use. If the team cannot show that path without guesswork, the model pack is not mature enough for serious banking reliance.
Banking practice note: documentation quality
For human in the loop checkpoints, documentation quality is not optional detail. It decides whether the bank can explain the model, defend the use and protect the customer. A model may be fast and accurate in a narrow test, but banking approval depends on whether the result is suitable for human oversight, decision accountability, high-impact review, exception handling, customer protection and operational control.
The practical test is to trace one item from model score through four-eyes control and into the business use. If the team cannot show that path without guesswork, the model pack is not mature enough for serious banking reliance.
Banking practice note: implementation evidence
For human in the loop checkpoints, implementation evidence is not optional detail. It decides whether the bank can explain the model, defend the use and protect the customer. A model may be fast and accurate in a narrow test, but banking approval depends on whether the result is suitable for human oversight, decision accountability, high-impact review, exception handling, customer protection and operational control.
The practical test is to trace one item from recommendation through evidence display and into the business use. If the team cannot show that path without guesswork, the model pack is not mature enough for serious banking reliance.
Banking practice note: monitoring threshold
For human in the loop checkpoints, monitoring threshold is not optional detail. It decides whether the bank can explain the model, defend the use and protect the customer. A model may be fast and accurate in a narrow test, but banking approval depends on whether the result is suitable for human oversight, decision accountability, high-impact review, exception handling, customer protection and operational control.
The practical test is to trace one item from reason code through override capture and into the business use. If the team cannot show that path without guesswork, the model pack is not mature enough for serious banking reliance.
Banking practice note: override review
For human in the loop checkpoints, override review is not optional detail. It decides whether the bank can explain the model, defend the use and protect the customer. A model may be fast and accurate in a narrow test, but banking approval depends on whether the result is suitable for human oversight, decision accountability, high-impact review, exception handling, customer protection and operational control.
The practical test is to trace one item from source evidence through escalation rule and into the business use. If the team cannot show that path without guesswork, the model pack is not mature enough for serious banking reliance.
Banking practice note: complaint feedback
For human in the loop checkpoints, complaint feedback is not optional detail. It decides whether the bank can explain the model, defend the use and protect the customer. A model may be fast and accurate in a narrow test, but banking approval depends on whether the result is suitable for human oversight, decision accountability, high-impact review, exception handling, customer protection and operational control.
The practical test is to trace one item from policy rule through materiality threshold and into the business use. If the team cannot show that path without guesswork, the model pack is not mature enough for serious banking reliance.
Banking practice note: customer harm
For human in the loop checkpoints, customer harm is not optional detail. It decides whether the bank can explain the model, defend the use and protect the customer. A model may be fast and accurate in a narrow test, but banking approval depends on whether the result is suitable for human oversight, decision accountability, high-impact review, exception handling, customer protection and operational control.
The practical test is to trace one item from case facts through review quality sampling and into the business use. If the team cannot show that path without guesswork, the model pack is not mature enough for serious banking reliance.
Banking practice note: regulatory evidence
For human in the loop checkpoints, regulatory evidence is not optional detail. It decides whether the bank can explain the model, defend the use and protect the customer. A model may be fast and accurate in a narrow test, but banking approval depends on whether the result is suitable for human oversight, decision accountability, high-impact review, exception handling, customer protection and operational control.
The practical test is to trace one item from customer-impact flag through training control and into the business use. If the team cannot show that path without guesswork, the model pack is not mature enough for serious banking reliance.
Banking practice note: third-party dependency
For human in the loop checkpoints, third-party dependency is not optional detail. It decides whether the bank can explain the model, defend the use and protect the customer. A model may be fast and accurate in a narrow test, but banking approval depends on whether the result is suitable for human oversight, decision accountability, high-impact review, exception handling, customer protection and operational control.
The practical test is to trace one item from materiality level through conflict-of-interest control and into the business use. If the team cannot show that path without guesswork, the model pack is not mature enough for serious banking reliance.
Banking practice note: change control
For human in the loop checkpoints, change control is not optional detail. It decides whether the bank can explain the model, defend the use and protect the customer. A model may be fast and accurate in a narrow test, but banking approval depends on whether the result is suitable for human oversight, decision accountability, high-impact review, exception handling, customer protection and operational control.
The practical test is to trace one item from review checklist through audit log and into the business use. If the team cannot show that path without guesswork, the model pack is not mature enough for serious banking reliance.
Banking practice note: incident response
For human in the loop checkpoints, incident response is not optional detail. It decides whether the bank can explain the model, defend the use and protect the customer. A model may be fast and accurate in a narrow test, but banking approval depends on whether the result is suitable for human oversight, decision accountability, high-impact review, exception handling, customer protection and operational control.
The practical test is to trace one item from reviewer identity through feedback loop and into the business use. If the team cannot show that path without guesswork, the model pack is not mature enough for serious banking reliance.
Banking practice note: retirement criteria
For human in the loop checkpoints, retirement criteria is not optional detail. It decides whether the bank can explain the model, defend the use and protect the customer. A model may be fast and accurate in a narrow test, but banking approval depends on whether the result is suitable for human oversight, decision accountability, high-impact review, exception handling, customer protection and operational control.
The practical test is to trace one item from decision note through human-review trigger and into the business use. If the team cannot show that path without guesswork, the model pack is not mature enough for serious banking reliance.
Banking practice note: legal classification
The practical test is to trace one item from override reason through role-based authority and into the business use. If the team cannot show that path without guesswork, the model pack is not mature enough for serious banking reliance.
Banking practice note: model purpose
The practical test is to trace one item from escalation record through four-eyes control and into the business use. If the team cannot show that path without guesswork, the model pack is not mature enough for serious banking reliance.
Banking practice note: customer population
The practical test is to trace one item from final action through evidence display and into the business use. If the team cannot show that path without guesswork, the model pack is not mature enough for serious banking reliance.
Banking practice note: source authority
The practical test is to trace one item from model score through override capture and into the business use. If the team cannot show that path without guesswork, the model pack is not mature enough for serious banking reliance.
Banking practice note: training data
The practical test is to trace one item from recommendation through escalation rule and into the business use. If the team cannot show that path without guesswork, the model pack is not mature enough for serious banking reliance.
Banking practice note: feature governance
The practical test is to trace one item from reason code through materiality threshold and into the business use. If the team cannot show that path without guesswork, the model pack is not mature enough for serious banking reliance.
Banking practice note: protected-class testing
The practical test is to trace one item from source evidence through review quality sampling and into the business use. If the team cannot show that path without guesswork, the model pack is not mature enough for serious banking reliance.
Banking practice note: proxy-variable review
The practical test is to trace one item from policy rule through training control and into the business use. If the team cannot show that path without guesswork, the model pack is not mature enough for serious banking reliance.
Banking practice note: adverse action reasons
The practical test is to trace one item from case facts through conflict-of-interest control and into the business use. If the team cannot show that path without guesswork, the model pack is not mature enough for serious banking reliance.
Banking practice note: reason-code mapping
The practical test is to trace one item from customer-impact flag through audit log and into the business use. If the team cannot show that path without guesswork, the model pack is not mature enough for serious banking reliance.
Banking practice note: explainability limits
The practical test is to trace one item from materiality level through feedback loop and into the business use. If the team cannot show that path without guesswork, the model pack is not mature enough for serious banking reliance.
Banking practice note: independent validation
The practical test is to trace one item from review checklist through human-review trigger and into the business use. If the team cannot show that path without guesswork, the model pack is not mature enough for serious banking reliance.
Banking practice note: effective challenge
The practical test is to trace one item from reviewer identity through role-based authority and into the business use. If the team cannot show that path without guesswork, the model pack is not mature enough for serious banking reliance.
Banking practice note: approval committee
The practical test is to trace one item from decision note through four-eyes control and into the business use. If the team cannot show that path without guesswork, the model pack is not mature enough for serious banking reliance.
Banking practice note: documentation quality
The practical test is to trace one item from override reason through evidence display and into the business use. If the team cannot show that path without guesswork, the model pack is not mature enough for serious banking reliance.
Banking practice note: implementation evidence
The practical test is to trace one item from escalation record through override capture and into the business use. If the team cannot show that path without guesswork, the model pack is not mature enough for serious banking reliance.
Banking practice note: monitoring threshold
The practical test is to trace one item from final action through escalation rule and into the business use. If the team cannot show that path without guesswork, the model pack is not mature enough for serious banking reliance.
Give a reviewer a real decision
A human checkpoint matters when the person has source evidence, authority, time and a defined set of actions. For a credit referral, show verified income, obligations, model score and reasons, policy requirements and unresolved data flags. Record whether the analyst approved, declined, requested evidence or escalated, with rationale. A button clicked after the system has already committed the customer outcome is not a meaningful review.
For a sanctions candidate, retain list version, matched identifiers and source documents. A generated summary may help navigation but should not hide contradictory evidence. Test workload and deadlines: sending every ambiguous case to a small team can cause automatic delays or rubber-stamping. Measure override patterns, review quality and customer effects. When the model is unavailable, the bank's approved manual process and required controls must still function.
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