def _undouble(self, word):
if (<EOL>len(word) > <NUM_LIT:1><EOL>and word[-<NUM_LIT:1>] == word[-<NUM_LIT:2>]<EOL>and word[-<NUM_LIT:1>] in {'<STR_LIT:d>', '<STR_LIT:k>', '<STR_LIT:t>'}<EOL>):<EOL><INDENT>return word[:-<NUM_LIT:1>]<EOL><DEDENT>return word<EOL>
Undouble endings -kk, -dd, and -tt.

        Parameters
        ----------
        word : str
          The word to stem

        Returns
        -------
        str
            The word with doubled endings undoubled