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# How does a new attribute like adjective='manxsome' become a kwargs dictionary (or its item)?

Is it all about those 2 stars (**), which make all the magic? Or all that those 2 stars do is show that we have a dictionary here?

PLUS

Let's use this function as example:

```def add(a, b):
return a + b
```

There're two ways you can call this function.

First way is by passing in positional arguments.

```print(add(3,4))
```

Second way, by keyword arguments.

```print(add(b=4, a=3))
```

(notice that by passing keyword arguments, you are free to place them out of order). For the `add` function, it takes EXACTLY 2 arguments, passing in more or less arguments and you'll get an ArugmentError runtime exception.

Sometimes it's useful to write a function that accept any numbers of arguments.

```def foo(*args, **kwargs):
for i in args: print(i)
for key, value in kwargs.items(): print(key, value)
```

In this function definition, There's no required arguments, but there're `*args`, and `**kwargs` here. I can call this function by supply any numbers of arguments, whether they are keyword argument or positional arguments.

```foo(3, 4, 9, "yo", keyword1=3, keyword2="hello")
```

So when I call the function like above, 3, 4, 9, "yo" as positional arguments, they get stored in `args` tuples, and keyword1=3, keyword2="hello" as keyword argument get stored in `kwargs` dictionary, so that you can do something about them in the function body. (In this `foo` case, I just print them all out).

Hope that helps.

Thanks William Li, you really made it sound so simple. Love the way you broke it down.