Is there an overhead when nesting functions in Python?

Question

In Python, if I have a child function within a parent function, is the child function \"initialised\" (created) every time the parent function is called? Is there any overhe

Answer 1

Yes. This enables closures, as well as function factories.

A closure causes the inner function to remember the state of its environment when called.

def generate_power(number):

    # Define the inner function ...
    def nth_power(power):
        return number ** power

    return nth_power

Example

>>> raise_two = generate_power(2)
>>> raise_three = generate_power(3)

>>> print(raise_two(3))
8
>>> print(raise_three(5))
243
"""