a = "hellllllllllooooooooooooo"
    match = re.search('(.)\1+', a)

    if match:
        print 'found'
        print re.sub('(.)\1+', '\1', a)
        print re.sub('(.)\1+', '\1\1', a)
    else:
        print 'not found'

helo
helloo

def doppelstring(s):
    letter_groups = ((val, list(group)) for val, group in itertools.groupby(s))
    max_vector = ((val, min(len(group), 2)) for val, group in letter_groups)
    vector_components = ([dim * (l + 1) for l in range(maxlen)] for dim, maxlen in max_vector)
    return [''.join(letters) for letters in itertools.product(*vector_components)]

def doppelstring_(s):
    max_vector = ((val, min(len(list(group)), 2)) for val, group in itertools.groupby(s))
    vector_components = ([dim * (l + 1) for l in range(maxlen)] for dim, maxlen in max_vector)
    return [''.join(letters) for letters in itertools.product(*vector_components)]

import re

def permute(seq):
    if len(seq) < 2:
        yield seq
    else:
        for tail in permute(seq[2:]):
            yield seq[:2] + tail
            yield seq[:2] + seq[1:2] + tail

text = "hellllllllllooooooooooooo"
seq = re.split('(.)\1+', text)

for result in permute(seq):
    print ''.join(result)

def squeeze(str, chars='abcdefghijklmnopqrstuvwxyz', min=1):
    new_str = str
    for c in chars:
        new_str = new_str.replace(c*(1+min),c*min)
    if new_str != str:
        new_str = squeeze(new_str, min=min)
    return new_str

>>> squeeze('aaaabbbbcccc')
'abc'
>>> squeeze('aaaabbbbcccc', min=2)
'aabbcc'

def squeezutations(str):
    str = squeeze(str, chars=set(str), min=2)
    for j,k in ((j,k) for j in range(2,0,-1) for k in range(1,3)):
        for c in set(str):
            yield squeeze(squeeze(str, chars=c, min=k), chars=set(str)-set(c), min=j )

>>> set(squeezutations('appppppppple'))
set(['apple', 'aple'])