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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 base_url(self, space_id, content_type_id, environment_id=None, **kwargs):
 """ Returns the URI for the editor interface. """


        return "spaces/{0}{1}/content_types/{2}/editor_interface".format(
            space_id,
            '/environments/{0}'.format(environment_id) if environment_id is not None else '',
            content_type_id
        )