gistfile1.py

>>> english = set(open('/usr/share/dict/words').read().splitlines())
>>> left_hand = 'qwertasdfgzxcvb'
>>> words_typeable_by_left_hand = [w for w in english if all(c in left_hand for c in w)]
>>> print max(words_typeable_by_left_hand,key = lambda w: len(w))
reverberates