message: Fix num_towers to be num_cores rather than cores_per_host
diff: @@ -109,6 +109,7 @@ class TPUStrategy(one_device_strategy.OneDeviceStrategy):
  """Enqueue ops for one iteration."""
  control_deps = []
  sharded_inputs = []
  + # TODO(sourabhbajaj): Add support for TPU pods
  with ops.device(self._host):
  for _ in range(self.num_towers):
  # Use control dependencies to ensure a deterministic ordering.
  @@ -261,4 +262,4 @@ class TPUStrategy(one_device_strategy.OneDeviceStrategy):
  @property
  def num_towers(self):
  - return self._num_cores_override or self._tpu_metadata.num_of_cores_per_host
  + return self._num_cores_override or self._tpu_metadata.num_cores
  