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Functions & basics

Reusable building blocks — parameters, returns, scope, and clear function design.

5 matches

Chain Generators with yield from in Python

Combine multiple generators into one seamless sequence using the `yield from` delegation syntax in Python.

def numbers():
    yield 1
    yield 2
    yield 3

def letters():
    yield 'a'
    yield 'b'
    yield 'c'

def combined():
    yield from numbers()
    yield from letters()

if __name__ == "__main__":
    print(list(combined()))

16 0 Open

Functions & basics easy

How to Build Partial Functions with functools.partial in Python

Create reusable partial functions that pre-fill arguments using functools.partial, like making square and cube functions from a general power function.

functools partial higher-order-functions

Python

```python
from functools import partial

def power(base, exponent):
    """Calculate base raised to the exponent power."""
    return base ** exponent

# Create partial functions for common powers
square = partial(power, exponent=2)
cube = partial(power, exponent=3)

if __name__ == "__main__":
    squares = [square(x)…

13 0 Open

Functions & basics easy

How to Create an Iterator Class with Dunder Methods in Python

A minimal Counter class implementing __iter__ and __next__ to act as a self-iterating iterator, yielding numbers from start to end-1.

iterators dunder-methods class

Python

class Counter:
    def __init__(self, start=0, end=5):
        self.current = start
        self.end = end

    def __iter__(self):
        return self

    def __next__(self):
        if self.current >= self.end:
            raise StopIteration
        value = self.current
        self.current += 1
        return val…

14 0 Open

Functions & basics easy

How to Return Multiple Values from a Python Function

This code demonstrates how a Python function can return multiple values as a tuple, and how to unpack that tuple into individual variables.

functions tuple return-values

Python

def get_user_stats(name, score, level):
    """Return multiple values as a tuple."""
    return name, score, level

if __name__ == "__main__":
    result = get_user_stats("Alice", 95, 3)
    print(result)
    print(type(result))
    
    # Unpacking into individual variables
    player_name, player_score, player_level…

16 0 Open

Functions & basics easy

How to Use Python's next() Builtin with a Default Sentinel Value

A wrapper function that returns the next item from an iterator, or a default sentinel value when the iterator is exhausted.

next iterator sentinel

Python

def get_next_or_default(iterator, default=None):
    """Return the next item from an iterator, or default if exhausted."""
    return next(iterator, default)


if __name__ == "__main__":
    fruits = iter(["apple", "banana", "cherry"])
    
    print(get_next_or_default(fruits))           # apple
    print(get_next_or…

14 0 Open

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