message: replaced builtin `all` by `np.all`
diff: @@ -625,7 +625,7 @@ class Flatten(Layer):
  if not input_shape:
  output_shape = tensor_shape.TensorShape([1])
  output_shape = [input_shape[0]]
  - if all(input_shape[1:]):
  + if np.all(input_shape[1:]):
  output_shape += [np.prod(input_shape[1:])]
  else:
  output_shape += [None]
  