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Args and Kwargs

In Python, *args and **kwargs allow a function to accept and deal with a variable number of arguments.

*args collects positional arguments into a tuple
**kwargs collects keyword (named) arguments into a dictionary

def print_arguments(*args: object, **kwargs: object) -> None:
    print(f"Positional arguments: {args}")
    print(f"Keyword arguments: {kwargs}")


print_arguments("hello", "world", a=1, b=2)
# Positional arguments: ('hello', 'world')
# Keyword arguments: {'a': 1, 'b': 2}

Positional Arguments

Positional arguments are the ones you're already familiar with, where the order of the arguments matters. Like this:

def sub(a: int, b: int) -> int:
    return a - b


# a=3, b=2
res: int = sub(3, 2)
# res = 1

Keyword Arguments

Keyword arguments are passed in by name. Order does not matter. Like this:

def sub(a: int, b: int) -> int:
    return a - b


res: int = sub(b=3, a=2)
# res = -1
res = sub(a=3, b=2)
# res = 1

A Note on Ordering

Any positional arguments must come before keyword arguments. This will not work:

sub(b=3, 2)

Assignment

At Doc2Doc, we need better internal debugging tools. Complete the args_logger function. It takes a variable number of positional and keyword arguments and prints them to the console.

Print each positional argument sequentially using numbers and periods as list markers, starting with 1. . For example:
```
args_logger("what's", "up", "doc")
```
prints to the console:
```
1. what's
2. up
3. doc
```
Sort the keyword arguments alphabetically by key with the sorted function.
Then print the sorted keyword arguments using asterisks (*) as list markers, and with a colon (:) between the key and value. For example:
```
args_logger("hi", "there", age=17, date="July 4 1776")
```
prints to the console:
```
1. hi
2. there
* age: 17
* date: July 4 1776
```

Tips

Don't feel guilty about using loops.
kwargs is a dictionary, not a list. My recommendation is to use the .items() method to get the key-value pairs as a list of tuples, then sort that list before printing.
When you call sorted on a list of tuples, by default it sorts by the first item in each tuple (which is what you want here).