nltk

input

The cat is walking in the bedroom,A dog was runningacross the kitchen.

output

(S
  The/DT
  cat/NN
  is/VBZ
  walking/VBG
  in/IN
  the/DT
  bedroom/NN
  ,/,
  A/NNP
  dog/NN
  was/VBD
  runningacross/IN
  the/DT
  kitchen/NN
  ./.)