python regular expression to remove repeated words

Non- regex solution using itertools.groupby:

>>> strs = "this is just is is"
>>> from itertools import groupby
>>> " ".join([k for k,v in groupby(strs.split())])
'this is just is'
>>> strs = "this just so so so nice" 
>>> " ".join([k for k,v in groupby(strs.split())])
'this just so nice'

text = re.sub(r'\b(\w+)( \1\b)+', r'\1', text) #remove duplicated words in row

The \b matches the empty string, but only at the beginning or end of a word.