Python Lessons from Scratch | Python Functions: def and lambda (basics + examples)
In this video from the "Python Lessons from Scratch" series, we explore functions in Python: how to write functions using def, how to return a result using return, how to work with parameters and arguments, and what lambda functions are and where they are actually used.
Functions are the foundation of programming: they help break code down, reuse logic, and make programs clear and maintainable. If you learn to write functions correctly, it will be much easier to learn lists, dictionaries, classes, working with files, and any practical projects.
In this lesson, you will learn:
What a function is and why it is needed;
def syntax: function name, parameters, function body;
the difference between print() and return (why this is important for beginners);
positional and named arguments;
default parameter values;
variable scope (local and global);
how to write "pure" functions and how to test the result;
what lambda is in Python, its syntax, and limitations; When lambda is appropriate (short functions, sorting, map/filter – at a basic level).
We'll also look at practical examples:
a calculation function,
a string processing function,
an example of sorting with key=lambda ...,
typical beginner mistakes: forgetting a return statement, incorrect parameters, name conflicts, an unnecessary print statement, etc.
This lesson is suitable for:
beginners learning Python from scratch;
schoolchildren/students;
those who want to write structured code and understand program logic. 👍 If you found this video helpful, give it a like.
💬 Tell me in the comments what you don't understand: return, default parameters, or lambda—I'll make more examples.
🔔 Subscribe—more on modules, working with files, and mini-projects.
Hashtags:
#Python #PythonFunctions #def #lambda #PythonLessons
On this page of the site you can watch the video online Python Lessons from Scratch | Python Functions: def and lambda (basics + examples) with a duration of hours minute second in good quality, which was uploaded by the user ProGamer 25 June 2026, share the link with friends and acquaintances, this video has already been watched 30 times on youtube and it was liked by 2 viewers. Enjoy your viewing!
