Python | Inner functions in python

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Defining a function inside another function

n Python, it is possible to define a function inside another function. This is known as a nested function or an inner function. Here is an example:

def outer_function(x):

def inner_function(y):

return x + y

return inner_function

add_five = outer_function(5)

result = add_five(3)

print(result)

In this example, we define the outer_function that takes an argument x. Inside this function, we define the inner_function that takes an argument y and returns the sum of x and y.

We then return the inner_function from the outer_function. We can now assign the outer_function to a variable add_five with an argument of 5. This creates a new function that adds 5 to its argument. Finally, we call this new function with an argument of 3 and print the result, which is 8.

Defining a function inside another function can be useful in situations where the inner function is only needed within the context of the outer function. It can also help to keep the code organized and prevent naming conflicts with other functions or variables outside the scope of the outer function.