What is the difference between assert and raise in Python?
Antek N

In Python,assert andraise are both used to handle exceptional situations or errors in code, but they have different purposes and behaviors. Here's a detailed explanation of the differences betweenassert andraise: Assert: - Purpose: Theassert statement is used for debugging and sanity checks during development. It is primarily used to test assumptions about the code and validate conditions that should always be true. It helps uncover potential bugs or logical errors in the code. - Syntax: Theassert statement takes a condition as its argument and an optional error message. If the condition evaluates toFalse, anAssertionError exception is raised, halting the program's execution. - Behavior: Theassert statement is typically used to validate conditions that should be true at a specific point in the code. If the condition is not true, the program is terminated, and anAssertionError is raised, indicating that an assumption about the code has been violated. It is primarily used for debugging and development purposes and is often removed or disabled in production code. - Example:

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def divide(a, b):
    assert b != 0, "Denominator must be non-zero"
    return a / b

result = divide(10, 0)

In this example, theassert statement checks if the denominatorb is non-zero. If the condition is not satisfied, the program raises anAssertionError with the provided error message. Raise: - Purpose: Theraise statement is used to explicitly raise exceptions in Python. It allows you to raise built-in or custom exceptions to handle error conditions or exceptional situations in your code. - Syntax: Theraise statement is followed by an exception type or an instance of an exception class. Optionally, you can provide an error message or additional information about the exception. - Behavior: Theraise statement is used when you encounter an error or exceptional situation in your code that cannot be handled locally. By raising an exception, you transfer control to an exception handler that can handle the raised exception. This allows you to gracefully handle errors and control the flow of your program. - Example:

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def divide(a, b):
    if b == 0:
   raise ZeroDivisionError("Denominator must be non-zero")
    return a / b

try:
    result = divide(10, 0)
except ZeroDivisionError as e:
    print(str(e))

In this example, theraise statement is used to raise aZeroDivisionError exception when the denominatorb is zero. The exception is then caught using atry-except block, allowing you to handle the error and provide a meaningful error message. Summary: In summary,assert is primarily used for debugging and sanity checks during development, allowing you to test assumptions about the code and validate conditions that should be true. It raises anAssertionError if the condition is not satisfied. On the other hand,raise is used to explicitly raise exceptions to handle error conditions or exceptional situations in your code. It allows you to raise built-in or custom exceptions and transfer control to an exception handler. Understanding the differences betweenassert andraise enables you to handle exceptional situations effectively and ensure the robustness of your code. Choose the appropriate statement based on the specific requirements and context of your program.

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