Python **closures** occur when an <u>inner function is wrapped inside an outer function</u>, effectively referencing a value from the outer scope. They're useful for circumventing global variables.

**Closures** are useful when you have a few methods to use but not enough to make a whole class. They help keep things simple and clean. But, if you have a lot of methods and attributes to manage, it's better to use a class instead. 

Let's look at some examples to understand this better.

def calculate_income(percent):
    def annual_income(amount):
        return amount * percent / 100
    return annual_income # function returned by outer function

interest_rate_3 = calculate_income(3) # function assigned to the variable
interest_rate_7 = calculate_income(7)

print(interest_rate_3(1500))
print(interest_rate_3(2000))

print(interest_rate_7(1500))
print(interest_rate_7(2000))

This function calculates annual income for a cash deposit. The closure functionality allows us <u>to store a function in a variable with a specific percentage value</u>, enabling us to reuse it multiple times. 

In summary, closures allow you to create and return functions that "remember" values from their enclosing scope, and this is especially useful for creating specialized functions with predefined behavior based on certain parameters.

In this course, you will learn advanced topics such as function arguments, iterators, generators, closures, and decorators. Dozens of practice exercises will help you grasp these topics.

You'll find this topic enjoyable, and you'll learn how to pack and unpack values in a single assignment.

Explore the power of Python's function arguments, *args, **kwargs, and learn how to effectively use functions as arguments.

Discover the higher-order functions and how functions can be passed as arguments to other functions in programming.

What is variable scope, and how did we manage without it before? This topic is essential for understanding the following subjects: Closures and Decorators. I assure you that this topic will be both enjoyable and practical. You will gain knowledge about local, nonlocal, and global variables.

This section provides an in-depth exploration of Python decorators, a powerful feature that allows for the modification and enhancement of function behavior. Participants will learn how to write their own decorators, understand built-in decorators, and apply decorators in practical scenarios.

Intermediate Python Techniques

Closures