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Table of Contents

  • Getting to Know Assertions in Python
    • What Are Assertions?
    • What Are Assertions Good For?
    • When Not to Use Assertions?
  • Understanding Python’s assert Statements
    • The Syntax of the assert Statement
    • The AssertionError Exception
  • Exploring Common Assertion Formats
  • Documenting Your Code With Assertions
  • Debugging Your Code With Assertions
    • An Example of Debugging With Assertions
    • A Few Considerations on Debugging With Assertions
  • Disabling Assertions in Production for Performance
    • Understanding the __debug__ Built-in Constant
    • Running Python With the -O or -OO Options
    • Setting the PYTHONOPTIMIZE Environment Variable
    • Running Python in Optimized Mode
  • Testing Your Code With Assertions
  • Understanding Common Pitfalls of assert
    • Using assert for Data Processing and Validation
    • Handling Errors With assert
    • Running assert on Expressions With Side Effects
    • Impacting Performance With assert
    • Having assert Statements Enabled by Default
  • Conclusion
  • Frequently Asked Questions

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