Function Definition:

Function is a block of reusable code designed to carry out a selected undertaking.

Functions help in modularizing code, making it greater prepared, readable, and maintainable.

                                  
                                    x = 10

if x > 10:
    print("x is greater than 10")
elif x == 10:
    print("x is equal to 10")
else:
    print("x is less than 10")
                                  
                                

• The def key-word is used to define a function.
• greet is the name of the function.
• (name) is the parameter that the function takes. Functions can have multiple parameters.
• The colon : indicates the beginning of the function's code block.

Function Call:

Function call is the manner of executing a characteristic that has been described earlier in the code.

                                      
                                        greet("Alice")
# Output: Hello, Alice!
                                      
                                    

This is the manner you call (invoke) a function. You offer the critical arguments in the parentheses.

Return Statement:

The return assertion is used to exit a characteristic and return a rate to the caller.

When a characteristic is called and encounters a pass again announcement, it immediately stops executing, and the desired fee is sent once more to the factor in the code wherein the characteristic have become known as.

                                      
                                        def add_numbers(a, b):
    """This function adds two numbers and returns the result."""
    result = a + b
    return result
                                      
                                    

The return statement is used to return a value from the function.

                                      
                                        sum_result = add_numbers(3, 5)
print(sum_result)
# Output: 8
                                      
                                    

Default Parameters:

Default values for parameters in a function. Default parameters will let you outline a price that a parameter will take if no argument is provided for it inside the route of the characteristic call. This is useful while you want a function to work with a default rate if the patron could no longer provide a particular one.

                                      
                                        def greet_with_message(name, message="Hello"):
    """This function greets a person with an optional custom message."""
    print(message + ", " + name + "!")
                                      
                                    

In this case, message is a parameter with a default fee. If no cost is furnished for message, it defaults to "Hello".

                                      
                                        greet_with_message("Bob")
# Output: Hello, Bob!

greet_with_message("Bob", "Good morning")
# Output: Good morning, Bob!

                                      
                                    

Variable Scope:

Variable scope in Python refers to the region or context in which a variable is accessible and can be modified.

The scope determines where in the code a variable can be used and whether it can be accessed or modified from different parts of the program. Python has two main types of variable scope:

                                      
                                        global_variable = 10

def print_global_variable():
    """This function prints the global variable."""
    print(global_variable)

print_global_variable()
# Output: 10
                                      
                                    

Variables defined outside of any function have a global scope and can be accessed within functions.

Docstring:

A docstring is a string literal that occurs as the first statement in a module, function, class, or method definition.

It is used to provide documentation and information about the purpose, behavior, and usage of the code it describes. Docstrings are not just comments; they are accessible through the __doc__ attribute at runtime, making them a form of documentation that can be programmatically retrieved.

                                      
                                        def square(number):
    """This function squares the input number."""
    return number ** 2
                                      
                                    

A docstring is a string that provides documentation for the function.

It is used to describe the purpose of the function, parameters, and return values.

Lambda Functions (Anonymous Functions):

A lambda feature, moreover called an nameless characteristic or a lambda expression, is a concise way to create small, unnamed talents. Lambda features are defined the use of the lambda keyword, located with the aid of a list of parameters, a colon, and an expression. The quit end result of the expression is the move again price of the lambda characteristic.

                                      
                                        square = lambda x: x ** 2
                                      
                                    

Lambda skills are short, anonymous functions defined the usage of the lambda key-word.

                                      
                                        result = square(4)
print(result)
# Output: 16
                                      
                                    

These are only some examples of the various techniques you can outline and use features in Python. Functions are a powerful tool in programming, allowing you to shape code, make it greater readable, and reuse desirable judgment.