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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 remove_read_more_sep(self, raw_content):
 """ Removes the first read_more_sep that occurs in raw_content. Subclasses should call this method to preprocess raw_content. """

        if self._read_more_exp is None:
            return raw_content

        sp = self._read_more_exp.split(raw_content, maxsplit=1)
        if len(sp) == 2 and sp[0]:
            result = '\n\n'.join((sp[0].rstrip(), sp[1].lstrip()))
        else:
            result = raw_content
        return result