PracticalPy

Some practical python technique

include

add command line argument_.py support.
```
$ python argument.py 1 2 3 --sum
```

log message and write to file logger_.py

$ python logger_.py
# alternatively
$ python logger_.py --info

C extension support via CPython

(cExtension)$ python setup.py build_ext --inplace

from cExtension.demo import add
add(1,2)   // 3