def get_installed_pypackages():
    return {p.project_name.lower(): p for p in pkg_resources.working_set}
def modify(self, pmtu):
        self.pmtu = pmtu
        self._test.vapi.ip_path_mtu_update(pmtu={'nh': self.nh,
                                                 'table_id': self.table_id,
                                                 'path_mtu': self.pmtu})
        return self