*args vs **kwargs

*args and **kwargs let a function accept a variable number of arguments.

• *args: extra positional arguments as a tuple.
• **kwargs: extra keyword arguments as a dict.
• Names args/kwargs are convention; the * / ** are what matter.

Parameter order (simplified): normal params → *args → keyword-only → **kwargs.

def report(title, *args, urgent=False, **kwargs):
    print("title:", title)
    print("args:", args)
    print("urgent:", urgent)
    print("kwargs:", kwargs)

report("ETL", "orders", "payments", urgent=True, owner="de-team")
# title: ETL
# args: ('orders', 'payments')
# urgent: True
# kwargs: {'owner': 'de-team'}

# Unpacking when calling
cols = ["a", "b"]
opts = {"sep": ",", "end": "!\n"}
print(*cols, **opts)  # a b!

def forward(*args, **kwargs):
    return report("proxy", *args, **kwargs)

Use them for wrappers, decorators, and flexible APIs. Prefer explicit parameters when the interface is stable and known.