def get_policy(observations, hparams):
  """Get a policy network.

  Args:
    observations: Tensor with observations
    hparams: parameters

  Returns:
    Tensor with policy and value function output
  """
  policy_network_lambda = hparams.policy_network
  action_space = hparams.environment_spec.action_space
  return policy_network_lambda(action_space, hparams, observations)