Python Functions Tutorial

1. What is Function in Python?

Now we will consider what a function in Python and some basic techniques used to create functions is: what are the arguments of the function, what is the return value of the function, what is the body of the function, and how to use the function in the code.

What Is Function?

Challenge: Building functions

2. Positional and Optional Arguments

Python is a fairly flexible language in terms of creating functions. This is especially true in setting function arguments - there are several different types of function arguments, and you can choose any of them depending on the problem you are solving. Let's now take a closer look at them.

Positional Arguments

Challenge: Positional Arguments

Optional Arguments

Challenge: Optional Arguments

3. Arbitrary Arguments

This section of the Python course covers *args and **kwargs, which allow you to handle variable numbers of positional and keyword arguments in functions. `*args` lets you pass any number of positional arguments, making functions more flexible. **kwargs allows you to pass any number of keyword arguments as a dictionary, which facilitates handling complex data structures efficiently.

Arbitrary Arguments

Arbitrary Keyword Arguments

Combination of Positional and Optional Arguments

4. Function Return Value Specification

The return value of a function is the direct result of the execution of the function, which we can use in the program. There are several types of function return values - now we will consider the most commonly used.

Single Return Value

Multiple Return Values

None Return Value

Generator Functions

Challenge: Traffic lights

5. Recursion and Lambda Functions

Now it's time to consider additional topics to help make your functions more flexible and solve more complicated tasks. You will understand recursion, lambda functions, and some basics principles of writing effective and maintainable functions.

Recursion

Challenge: Pyramid

Lambda Functions

Immediately Invoked Lambda Expression

Writing Effective and Maintainable Functions

Arbitrary Keyword Arguments

In programming, there's a special syntax for passing any number of named parameters to a function. This syntax is called **kwargs.

**kwargs allows a function to accept any number of named arguments and treat them as a dictionary.

In this example, **kwargs receives named arguments and prints their keys and values.

Note
The .items() method is used to obtain a list of key-value pairs (items) from a dictionary in Python. Each element in this list is represented as a tuple (key, value).

Task

Fill in the blanks (___) in the function definition so that it can accept a variable number of key-value pairs representing item names and their costs using keyword arguments **kwargs.
Fill in the blanks (___) in the loop to correctly calculate the total cost of the items stored in the **kwargs variable.

Everything was clear?

Section 3. Chapter 2

Course Content

Python Functions Tutorial

1. What is Function in Python?

What Is Function?Challenge: Building functions Arguments Return Value Function Body Built-in Functions

2. Positional and Optional Arguments

Positional Arguments Challenge: Positional Arguments Optional Arguments Challenge: Optional Arguments

3. Arbitrary Arguments

Arbitrary Arguments Arbitrary Keyword Arguments Combination of Positional and Optional Arguments

4. Function Return Value Specification

Single Return Value Multiple Return Values None Return Value Generator Functions Challenge: Traffic lights

5. Recursion and Lambda Functions

Recursion Challenge: Pyramid Lambda Functions Immediately Invoked Lambda Expression Writing Effective and Maintainable Functions

Python Functions Tutorial

Arbitrary Keyword Arguments

In programming, there's a special syntax for passing any number of named parameters to a function. This syntax is called **kwargs.

**kwargs allows a function to accept any number of named arguments and treat them as a dictionary.

In this example, **kwargs receives named arguments and prints their keys and values.

Note
The .items() method is used to obtain a list of key-value pairs (items) from a dictionary in Python. Each element in this list is represented as a tuple (key, value).

Task

Fill in the blanks (___) in the function definition so that it can accept a variable number of key-value pairs representing item names and their costs using keyword arguments **kwargs.
Fill in the blanks (___) in the loop to correctly calculate the total cost of the items stored in the **kwargs variable.

Everything was clear?

Section 3. Chapter 2