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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def _mplain_word_separator(self):
 """ Get the word separator to split words in mplain format. :rtype: string """

        word_separator = gf.safe_get(self.parameters, gc.PPN_TASK_IS_TEXT_MPLAIN_WORD_SEPARATOR, u" ")
        if (word_separator is None) or (word_separator == "space"):
            return u" "
        elif word_separator == "equal":
            return u"="
        elif word_separator == "pipe":
            return u"|"
        elif word_separator == "tab":
            return u"\u0009"
        return word_separator