def load_installed_version(self):
        installed_packages = get_installed_pypackages()
        if self.package in installed_packages:
            self.version = "=={}".format(
                installed_packages[self.package].version)
def gradients(self, d_grads, g_grads):
      if self.d_grads is None:
          self.d_grads = [torch.zeros_like(_g) for _g in d_grads]
          self.g_grads = [torch.zeros_like(_g) for _g in g_grads]