NB question on global/local variables in functions

[Wolfgang]

> 
> First, avoid "from function import *" as it pollutes your namespace.  Either
> import specific symbols or just the module:
> 
>     from function import fun, fun1
>     import function

thanks for the hint! But what is the difference between
from module import *
	and
import module
?

> 
> Second, if you really must, add an __all__ list to function.py, generally
> right at the top:
> 
>     __all__ = ['fun', 'fun1']

I've read this already, but to keep the example short I've skipped that 
part.

> 
> (Note that __all__ is a list of strings.)  The "from star" import will only
> import the names in the __all__ list.  You can also "hide" individual names
> from a "from star" import by prefixing them with a single underscore (e.g.,
> "_c1" instead of "c1").
> 

the _ before the variable did the trick! Thanks a lot!

> Third, one of Python's key concepts is "we're all adults here".  You can't
> really and truly hide c1 and c2, so just act responsibly and don't mess with
> them from outside the function module.

It is more to prevent myself from my own stupidness by changing global 
variables incidentally.

Wolfgang