Python assert

The assert keyword confirms the truthiness of a given statement and is often used to facilitate development, document code, and debug.

Syntax

assert some_condition, assert_message

The assert keyword is followed by some_condition to be tested, such as validating a data type or membership within a given container. An optional assert_message can be added that will be printed when the assertion error is raised.

Example

The assert keyword can be used to validate a value (or evaluate some other condition):

fav_color = 'blue'

assert fav_color == 'red'

# Output: AssertionError

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Codebyte Example

The following example uses assert to evaluate if 'mud' is within the following list things_that_float:

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