python list comprehensions; compressing a list of lists?

Question

guys. I\'m trying to find the most elegant solution to a problem and wondered if python has anything built-in for what I\'m trying to do.

What I\'m doing is this. I

Answer 1

Google brought me next solution:

def flatten(l):
   if isinstance(l,list):
      return sum(map(flatten,l))
   else:
      return l