def __build_sequence(parts):
strand = parts[<NUM_LIT:4>]<EOL>seq_length = int(parts[<NUM_LIT:3>])<EOL>total_seq_len = int(parts[<NUM_LIT:5>])<EOL>start = (int(parts[<NUM_LIT:2>]) if strand == "<STR_LIT:+>"<EOL>else total_seq_len - int(parts[<NUM_LIT:2>]) - seq_length)<EOL>end = start + seq_length<EOL>remain = total_seq_len - end<EOL>return Sequence(parts[<NUM_LIT:1>], parts[<NUM_LIT:6>], start, end, strand, remain)<EOL>
Build a sequence object using the pre-tokenized parts from a MAF line.

    s -- a sequence line; has 6 fields in addition to 's':
            * source sequence,
            * start coord. of seq., zero-based. If -'ve strand, rel to start of
              rev. comp.
            * ungapped length of the sequence
            * strand
            * src size -- the full length of the source sequence
            * the sequence itself