import itertools
 
 def strip_common_prefix(text):
 		text = text.expandtabs(2).split('\n')
 		text = itertools.izip_longest(*text, fillvalue='')
 		text = list(itertools.dropwhile(lambda x: set(x) == set(' '), text))
 		return '\n'.join(''.join(x) for x in zip(*text))
 
 print strip_common_prefix('''   \n   asdasd\n    asdasd\n   asdasdasd''')