What is the purpose of the assert statement in Python?

        The assert statement in Python is used as a debugging aid to test a condition and trigger an error if the condition is not true. It takes an expression that is expected to be true and raises an AssertionError exception if it evaluates to false.

        The basic syntax of the assert statement is as follows:

assert expression, message

        where expression is the condition being tested and message is an optional string that will be displayed as the error message if the assertion fails.

        For example, if we want to check if a function square(x) returns the correct output for a given input, we can use the assert statement as follows:

def square(x):
    return x**2

assert square(2) == 4, "Error: square(2) should equal 4"

        If the square(2) does not equal 4, then the assert statement will raise an AssertionError with the message "Error: square(2) should equal 4".