recursive import in python
Question: in logging.py in my python library there are the lines:

    
    
    import logging
    

and:

    
    
    from logging import DEBUG, INFO, WARNING, ERROR, CRITICAL
    

I don't understand the meaning of importing logging within logging.py and also
where (DEBUG, INFO, WARNING, ERROR, CRITICAL) are defined?


Answer: it's importing `logging` from python standard library,
[link](https://docs.python.org/2/library/logging.html),

also [here](https://docs.python.org/2/library/logging.html#logging-levels) is
log levels in that page (DEBUG, INFO, ...)

