message: Stop double-normalizing pool_mode
diff: @@ -1206,7 +1206,7 @@ def pool2d(x, pool_size, strides=(1, 1), padding='valid', data_format=None, pool
  strides=strides,
  padding=padding,
  data_format=data_format,
  - pool_mode=_normalize_pool_mode(pool_mode))
  + pool_mode=pool_mode)
  @_log_call
  @@ -1216,7 +1216,7 @@ def pool3d(x, pool_size, strides=(1, 1, 1), padding='valid', data_format=None, p
  strides=strides,
  padding=padding,
  data_format=data_format,
  - pool_mode=_normalize_pool_mode(pool_mode))
  + pool_mode=pool_mode)
  @_log_call
  