# How to use BERT in seq2seq model? [closed]

I would like to use pretrained BERT as encoder of transformer model. The decoder has the same vocabulary as encoder and I am going to use shared embeddings. But I need <SOS>, <EOS> tokens which are not trained with BERT. How should I get them ? Can I use <CLS> token as <SOS> and <SEP> as <EOS> ? Or I have to create these two embeddings as trainable Variables and concatenate them to the decoder input / labels ?