RosettaCodeData/Task/Look-and-say-sequence/Python/look-and-say-sequence-2.py

>>> from itertools import groupby
>>> def lookandsay(number):
  return ''.join( str(len(list(g))) + k
            for k,g in groupby(number) )

>>> numberstring='1'
>>> for i in range(10):
  print numberstring
  numberstring = lookandsay(numberstring)