[Tutor] 2 problems in a small script

[Kent Johnson]

Dick Moores wrote:

>> If your interested, this could be done succinctly with set types. (no 
>> iterating required!) 

> Done. I had no idea set could be used that way! With a couple of 
> modifications, I used your ideas in both <buggy_For_Web5b.py> and 
> <getCrew_ForWeb2.py> (see the thread I started, < 
> http://www.nabble.com/An-idea-for-a-script-tf4603558.html#a13149808 >).

You might as well create the set of disallowed letters just once:
astr = set(ascii_letters + digits + '-_')

> 
>> OR...
>>
>> my_list = filter(well_formed, my_list)
> 
> I'll look into "filter".

The list comp form is actually preferred and IIRC filter() has been 
eliminated from Python 3.
> 
> A question:
> 
> Here's my(yours) well_formed():
> 
> def well_formed(word, astr):
>     """
>     Returns True if set(<a string>) - set(<a string>) is empty; False if 
> not.
>     """
>     return not set(word) - set(astr)
> 
> Is it OK to use <a string> like that in a docstring?

Sure why not?

Kent