UserWarning — Expert Examples
Default category for warnings issued by the user
UserWarning exception groups (Python 3.11+)
Using ExceptionGroup with UserWarning.
python
# Exception groups (Python 3.11+) import sys print(f"Python {sys.version}") # Exception hierarchy inspection print(f"UserWarning MRO:") for cls in UserWarning.__mro__: print(f" {cls.__name__}") # Exception attributes try: import warnings; warnings.warn("user warning", UserWarning) except UserWarning as e: print(f"\nException attributes:") print(f" args: {e.args}") print(f" __traceback__: {type(e.__traceback__)}") # Traceback manipulation import traceback tb_lines = traceback.format_exception(type(e), e, e.__traceback__) print(f" Traceback lines: {len(tb_lines)}")
Understanding the exception hierarchy and traceback system helps build robust error handling and debugging tools.
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