determine whether a pre-split string is a repeat-masker alignment header.

  headers have no special structure or symbol to mark them, so this is based
  only on the number of elements, and what data type they are.

def _rm_is_header_line(parts, n):
  """
  determine whether a pre-split string is a repeat-masker alignment header.

  headers have no special structure or symbol to mark them, so this is based
  only on the number of elements, and what data type they are.
  """
  if (n == 15 and parts[8] == "C"):
    return True
  if (n == 14 and parts[0].isdigit()):
    return True