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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 _parse_text(self, element_name, namespace=''):
 """ Returns the text, as a string, of the specified element in the specified namespace of the RSS feed. Takes element_name and namespace as strings. """

        try:
            text = self._channel.find('.//' + namespace + element_name).text
        except AttributeError:
            raise Exception(
                'Element, {0} not found in RSS feed'.format(element_name)
            )

        return text