Define functions, arguments, scope, recursion, and higher-order functions
01Stage 1 of the roadmap: FoundationsLearn to define and call Python functions, use parameters and return values, understand scope basics, and write reusable code with real-world examples.
Master Python function arguments - positional, keyword, default values, *args, **kwargs. Learn flexible function signatures used in real Python libraries.
Master Python lambda functions - anonymous one-line functions. Learn lambda syntax, use with sorted(), map(), filter(), and know when regular functions are better.
Understand Python variable scope - local, enclosing, global, built-in (LEGB). Learn closures, the global and nonlocal keywords, and avoid common scope bugs.
Master Python recursion - understand the call stack, base cases, and recursive patterns. Learn factorial, Fibonacci, and real-world recursive algorithms.
Master Python's functional tools - map(), filter(), and reduce(). Learn higher-order functions, combine them with lambda, and understand when comprehensions are better.