returning True, False or None

[Steven Bethard]

Raymond Hettinger wrote:
> "Steven Bethard"
> 
>>For a given list:
>>* If all values are None, the function should return None.
>>* If at least one value is True, the function should return True.
>>* Otherwise, the function should return False.
> 
>  . . .
> 
>>Right now, my code looks like:
>>
>>     if True in lst:
>>         return True
>>     elif False in lst:
>>         return False
>>     else:
>>         return None
>>
>>This has a light code smell for me though -- can anyone see a simpler
>>way of writing this?
> 
> 
> return max(lst)

Very clever!  Thanks!

Steve