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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 publish_extensions(self, handler):
 """Publish the Media RSS Feed elements as XML."""

        if isinstance(self.media_content, list):
            [PyRSS2Gen._opt_element(handler, "media:content", mc_element) for
             mc_element in self.media_content]
        else:
            PyRSS2Gen._opt_element(handler, "media:content",
                                   self.media_content)

        if hasattr(self, 'media_title'):
            PyRSS2Gen._opt_element(handler, "media:title", self.media_title)

        if hasattr(self, 'media_text'):
            PyRSS2Gen._opt_element(handler, "media:text", self.media_text)