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OOP & classes

Classes, instances, methods, dataclasses, and object-oriented design in Python.

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OOP & classes easy

How to define a custom exception class in Python with an error code attribute

Create a custom exception class with extra attributes like an error code, then raise and catch it in a try/except block.

exceptions classes error-handling
Python 
class UserNotFoundError(Exception):
    def __init__(self, user_id, error_code=404):
        self.user_id = user_id
        self.error_code = error_code
        super().__init__(f"User with ID {user_id} was not found (error code: {error_code})")

def find_user(user_id, users_db):
    if user_id not in users_db:
      …
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