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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def convert_tokens_to_ids(self, tokens):
 """Converts a sequence of tokens into ids using the vocab."""

        ids = []
        for token in tokens:
            ids.append(self.vocab[token])
        if len(ids) > self.max_len:
            logger.warning(
                "Token indices sequence length is longer than the specified maximum "
                " sequence length for this BERT model ({} > {}). Running this"
                " sequence through BERT will result in indexing errors".format(len(ids), self.max_len)
            )
        return ids