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Errors & debugging

Handle failures gracefully, raise helpful errors, and debug with confidence.

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Errors & debugging easy

How to define an exception hierarchy for domain errors in Python

Create a custom exception hierarchy with a base DomainError class and specific subclasses to handle validation, not-found, permission, and concurrency errors cleanly in Python apps.

exceptions domain-errors error-handling
Python 
class DomainError(Exception):
    """Base class for all domain errors."""
    pass

class ValidationError(DomainError):
    """Raised when input data fails validation rules."""
    pass

class NotFoundError(DomainError):
    """Raised when a requested entity does not exist."""
    pass

class PermissionDeniedError(Dom…
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