code: def error_check(options):
      
  
      compare = options.compare
      ensemble_paths = options.ensemble_paths
  
      if compare and len(ensemble_paths) > 2:
          print("\n Only 2 ensembles can be compared, {d} were specified\n".format(d=len(ensemble_paths)))
          sys.exit(1)
docs: Error check
      :rtype : object