wordninja

$ python
>>> import wordninja
>>> wordninja.split('derekanderson')
['derek', 'anderson']
>>> wordninja.split('imateapot')
['im', 'a', 'teapot']
>>> wordninja.split('heshotwhointhewhatnow')
['he', 'shot', 'who', 'in', 'the', 'what', 'now']
>>> wordninja.split('thequickbrownfoxjumpsoverthelazydog')
['the', 'quick', 'brown', 'fox', 'jumps', 'over', 'the', 'lazy', 'dog']

https://github.com/keredson/wordninja