def _truncate_seq_pair(tokens_a, tokens_b, max_length):
            """Truncates a sequence pair in place to the maximum length."""
            # This is a simple heuristic which will always truncate the longer
            # sequence one token at a time. This makes more sense than
            # truncating an equal percent of tokens from each, since if one
            # sequence is very short then each token that's truncated likely
            # contains more information than a longer sequence.

            if not tokens_b:
                max_length += 1

            while True:
                total_length = len(tokens_a) + len(tokens_b)
                if total_length <= max_length:
                    break
                if len(tokens_a) > len(tokens_b):
                    tokens_a.pop()
                else:
                    tokens_b.pop()

            tokens_a.append(tokenizer.sep_token)

            if tokens_b:
                tokens_b.append(tokenizer.sep_token)

            return tokens_a, tokens_b
Truncates a sequence pair in place to the maximum length.
utils_nlp/models/transformers/sequence_classification.py