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Python Closure




Imagine you have a function called outer_function that defines another function called inner_function inside it. Now, inner_function can access variables from the outer_function. When inner_function is returned from outer_function, it still remembers those variables even though outer_function has finished executing. This is the essence of a closure in Python.

Example Code:



In this example, outer_function takes a parameter x and defines inner_function inside it. inner_function can access x from the outer_function. When outer_function(10) is called, it returns inner_function, effectively creating a closure. Now, closure_example holds a reference to inner_function along with the value x (which is 10 in this case). When closure_example(5) is called, it adds 5 to the value of x (which is 10), resulting in 15.

So, a closure "closes over" the environment in which it was defined, allowing it to access variables from its enclosing scope even after that scope has finished executing.




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