No way to add shortened options (e.g. '-R/--recursive')

Would it be possible to create short names for default boolean arguments?

For example, if you have the following function:
```python
def hello(greeting, uppercase=False):
    greeting = greeting.upper() if uppercase else greeting
    print(greeting)
```

It would be nice to have the following usages:
`python hello.py Hey! -u`  
`python hello.py Hey! --uppercase`  