def PrintUsage(message):
 sys.stderr.write(_USAGE)
 if message:
  sys.exit(('\nFATAL ERROR: ' + message))
 else:
  sys.exit(1)

def PrintUsage ( message ) : sys . stderr . write ( _USAGE ) if message : sys . exit ( ( '\nFATAL ERROR: ' + message ) ) else : sys . exit ( 1 )
prints a brief usage string and exits .