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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 _default_body(self):
 """ If the body is not passed in by the user try to create one using the given data parameters. """

        if not self.data:
            return ""
        if self.content_type == 'application/json':
            import json
            return json.dumps(self.data)
        elif self.content_type == 'application/x-www-form-urlencoded':
            import urllib
            return urllib.urlencode(self.data)
        else:
            raise NotImplementedError(
                "You must manually encode the request "
                "body for '{}'".format(self.content_type)
            )