def __getitem__(self, key):
if isinstance(key, slice):<EOL><INDENT>word = key.start<EOL>morph = key.stop or self.morph1<EOL>tolerance_style = key.step or DEFAULT_TOLERANCE_STYLE<EOL><DEDENT>else:<EOL><INDENT>word, morph = key, self.morph1<EOL>tolerance_style = DEFAULT_TOLERANCE_STYLE<EOL><DEDENT>return self.allomorph(word, morph, tolerance_style)<EOL>
The syntax sugar to determine one of allomorphic morphs based on a
        word::

           eun = Particle(u'은', u'는')
           assert eun[u'나오'] == u'는'
           assert eun[u'모리안'] == u'은'