>>> "1 2     3".split()
['1', '2', '3']

>>> import re
>>> re.split(r'\b\s',  "1 2     3")
['1', '2', '    3']

>>> s = "1 2     3"
>>> s.split(' ', 2)
['1', '2', '    3']
>>> tuple(s.split(' ', 2)[-1])
(' ', ' ', ' ', ' ', '3')
>>>

re.split(r'\b\s',  "1 2     3")

s.split(' ', 2)

p = re.compile(r'(?<=\b)\s', re.U)
ls = p.split(u" я  у   z")
for e in ls:
    print "'%s'" % e