'Transform a human-readable string into a sequence of int ids.
The ids should be in the range [num_reserved_ids, vocab_size). Ids [0,
num_reserved_ids) are reserved.
EOS is not appended.
Args:
s: human-readable string to be converted.
Returns:
ids: list of integers'

def encode(self, s):

    return [(int(w) + self._num_reserved_ids) for w in s.split()]
