the actual rank `3` (shape = (None, None, 60)) is not equal to the expected rank `2`

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修改兼容TensorFlow2.x后报错：ValueError: For the tensor input_ids in scope <tensorflow.python.ops.variable_scope.VariableScope object at 0x7f3b268d56c0>, the actual rank 3 (shape = (None, None, 60)) is not equal to the expected rank 2