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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 _token_to_subtoken_ids(self, token):
 """Converts token to a list of subtoken ids. Args: token: a string. Returns: a list of integers in the range [0, vocab_size) """

    cache_location = hash(token) % self._cache_size
    cache_key, cache_value = self._cache[cache_location]
    if cache_key == token:
      return cache_value
    ret = self._escaped_token_to_subtoken_ids(
        _escape_token(token, self._alphabet))
    self._cache[cache_location] = (token, ret)
    return ret