src/transformers/models/prophetnet/tokenization_prophetnet.py/ProphetNetTokenizer/convert_tokens_to_string
class ProphetNetTokenizer:    def convert_tokens_to_string(self, tokens: str):
        """Converts a sequence of tokens (string) in a single string."""
        out_string = " ".join(tokens).replace(" ##", "").strip()
        return out_string