def issubtype(a, b):
 if issubclass(a, b):
  return True
 if (issubclass(a, (tuple, list, set)) and issubclass(b, Iterator)):
  return True
 if (issubclass(b, (tuple, list, set)) and issubclass(a, Iterator)):
  return True
 return False

def issubtype ( a , b ) : if issubclass ( a , b ) : return True if ( issubclass ( a , ( tuple , list , set ) ) and issubclass ( b , Iterator ) ) : return True if ( issubclass ( b , ( tuple , list , set ) ) and issubclass ( a , Iterator ) ) : return True return False
a custom issubclass .