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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 _clean_text(self, text):
 """Clean the text of extraneous punction. By default, ':', ';', and '.' are defined as stops. :param text: raw text :return: clean text :rtype : string """

        clean = []
        for char in text:
            if char in self.punc_stops:
                clean += '.'
            elif char not in self.punc:
                clean += char
            else:
                pass
        return (''.join(clean)).lower()