What is the use of "assert" in Python?

In Python, the assert statement is used to check if a certain condition is true, and if it is not true, raise an exception. The basic syntax of the assert statement is as follows:

assert some_condition, some_error_message

Here, some_condition is the condition that you want to check, and some_error_message is an optional error message that will be displayed if the condition is not true. If some_condition is true, nothing happens and the program continues to execute. If some_condition is false, an AssertionError is raised with the error message passed to the assert statement.

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For example, let's say you have a variable x that should always be positive, you can use assert statement to check this, like below:

x = -10
assert x > 0, "x should be positive"

This will raise an error: "AssertionError: x should be positive"

The assert statement is often used as a debugging aid, as it allows you to quickly check if a certain condition is true or not, and raises an error with a helpful message if it is not true. It should be noted that assert statements can be globally disabled by passing -O or -OO while running the python script or program , which can be useful in certain situations.