A decorator takes a function and returns a replacement, which then runs in its place on every call. @name above a def is shorthand for f = name(f).

from functools import wraps

def shout(fn):
    @wraps(fn)
    def wrapper(*args, **kwargs):
        result = fn(*args, **kwargs)
        return result.upper()
    return wrapper

@shout
def hello(name):
    return f"hi {name}"

• *args, **kwargs lets the wrapper accept whatever the original accepts.
• @wraps(fn) copies the name and docstring, which keeps tracebacks and tools readable.

For @repeat(3), you need one more layer: repeat(3) must return the decorator.

def repeat(n):
    def decorator(fn):
        @wraps(fn)
        def wrapper(*a, **k):
            for _ in range(n):
                out = fn(*a, **k)
            return out
        return wrapper
    return decorator

Write a decorator count_calls that stores how many times the function ran in a .calls attribute, starting at 0. Write a decorator factory retry(times) that calls the function up to times times in total, returning the first success and re-raising the last exception if all fail. Both keep the function's name.

The explanation opens here once every check passes.