docs: def _rm_get_names_from_header(parts):
    """
    get repeat and seq. name from repeatmasker alignment header line.
  
    An example header line is::
  
      239 29.42 1.92 0.97 chr1 11 17 (41) C XX#YY (74) 104 1 m_b1s502i1 4
  
    the genomic sequence name is always at position 4 (zero-based index); the
    name of the repeat is at position 9 if matching the reverse complement of
    the consensus sequence for the repeat and position 8 otherwise
  
    :param parts: the header line, as a tokenized list.
    :return: tuple of (name of genomic sequence, name of repeat sequence)
    """
    assert((parts[8] == "C" and len(parts) == 15) or (len(parts) == 14))
    return (parts[4], parts[8]) if len(parts) == 14 else (parts[4], parts[9])