code: def init_state(self, x):
      
      optim_state = {}
      optim_state["t"] = 0.
      optim_state["m"] = [tf.zeros_like(v) for v in x]
      optim_state["u"] = [tf.zeros_like(v) for v in x]
      return optim_state
docs: Initialize t, m, and u