were contributed by ydshieh.
EncoderDecoderConfig
[[autodoc]] EncoderDecoderConfig
EncoderDecoderModel
[[autodoc]] EncoderDecoderModel
    - forward
    - from_encoder_decoder_pretrained
TFEncoderDecoderModel
[[autodoc]] TFEncoderDecoderModel
    - call
    - from_encoder_decoder_pretrained
FlaxEncoderDecoderModel
[[autodoc]] FlaxEncoderDecoderModel
    - call
    - from_encoder_decoder_pretrained
