def find_dub_strs(mystring):
    grp = groupby(mystring)
seq = [(k, len(list(g)) >= 2) for k, g in grp]
allowed = 'aeioupt'
return rec_dubz('', seq, allowed=allowed)

def rec_dubz(prev, seq, allowed='aeiou'):
    if not seq:
        return [prev]
solutions = rec_dubz(prev + seq[0][0], seq[1:], allowed=allowed)
if seq[0][0] in allowed and seq[0][1]:
    solutions += rec_dubz(prev + seq[0][0] * 2, seq[1:], allowed=allowed)
return solutions
Remove letter duplicates that are in a row