Accepts a string and returns a list of strings of numeric LSB runlevels.

def GetRunlevelsNonLSB(states):
  """Accepts a string and returns a list of strings of numeric LSB runlevels."""
  if not states:
    return set()
  convert_table = {
      "0": "0",
      "1": "1",
      "2": "2",
      "3": "3",
      "4": "4",
      "5": "5",
      "6": "6",
      # SysV, Gentoo, Solaris, HP-UX all allow an alpha variant
      # for single user. https://en.wikipedia.org/wiki/Runlevel
      "S": "1",
      "s": "1"
  }
  _LogInvalidRunLevels(states, convert_table)
  return set([convert_table[s] for s in states.split() if s in convert_table])