What is a closure in Python?

        In Python, a closure is a function object that has access to variables in its enclosing lexical scope, even when the function is called outside that scope.

        In other words, a closure is a nested function that remembers values from its enclosing lexical scope, even if those values are not passed as arguments to the inner function. This allows the inner function to "close over" those values and use them later, even if the outer function has finished executing.

        Here is an example of a closure in Python:

def outer_function(x):
    def inner_function(y):
        return x + y
    return inner_function

closure = outer_function(10)
print(closure(5))  # Output: 15

        In this example, outer_function is a function that takes an argument x and returns a nested function inner_function. The inner_function takes an argument y and returns the sum of x and y.

        When we call outer_function(10), it returns the inner_function with x set to 10. We then assign this returned function to the variable closure. When we call closure(5), it returns the sum of x (which is 10) and y (which is 5), resulting in an output of 15.

        Note that x is a non-local variable in the inner_function because it is not defined within the function, but it is accessible due to the closure. The inner_function "closes over" the value of x from the outer_function and remembers it, even after outer_function has finished executing.