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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 describe_export(self, export_type):
 """ Fetch metadata for an export. - **export_type** is a string specifying which type of export to look up. Returns a :py:class:`dict` containing metadata for the export. """

        if export_type in TALK_EXPORT_TYPES:
            return talk.get_data_request(
                'project-{}'.format(self.id),
                export_type.replace('talk_', '')
            )[0]

        return self.http_get(
            self._export_path(export_type),
        )[0]