What do *args and **kwargs mean?

Question

Accepted Answer

They let a function accept a **variable number** of arguments:

- **`*args`** collects extra **positional** arguments into a **tuple**.
- **`**kwargs`** collects extra **keyword** arguments into a **dict**.

The names are convention only — the `*` and `**` do the work. In a definition the full parameter order is: positional, `*args`, keyword-only params, `**kwargs`. A bare `*` forces the parameters after it to be **keyword-only**.

The same operators **unpack** at the *call* site: `f(*some_list, **some_dict)` spreads a sequence into positional args and a dict into keyword args. This is how you forward arbitrary arguments through wrappers and decorators (`func(*args, **kwargs)`), which is why every decorator wrapper you write uses them.

**Interview tip:** distinguish the two contexts clearly — in a `def`, `*`/`**` *collect* (pack); at a *call*, they *spread* (unpack). The pass-through `(*args, **kwargs)` in a decorator wrapper is the canonical example.

What do *args and **kwargs mean?

Understand the problem

Attempt it yourself

Stuck? AI Nudge Available

Study the solution

The solution is waiting

Run the code

Join the discussion

Discussion (0)