>>> import MeCab
>>> m = MeCab.Tagger ("-O wakati")
Traceback (most recent call last):
File "<stdin>", line 1, in <module>
File "/Users/junichi/.pyenv/versions/3.6.1/lib/python3.6/site-packages/MeCab.py", line 307, in __init__
this = _MeCab.new_Tagger(*args)
RuntimeError
brew install mecab-ipadic