def unique_objects(object_list):
    """ Classifies objects by uniqueness. 
    Returns:
    list_of_unique: a list with a single instance of each unique objects
    inverse: an array of where in list_of_unique the object is found. list_of_unque[inverse] == object_list
    """
    
    set_of_unique = {t for t in object_list}
    list_of_unique = list(set_of_unique)
    
    
    def where(obj, list_of_unique):
        """ returns the location of the object obj in the list_of_unique. """
        for i,unique_object in enumerate(list_of_unique):
            if obj == unique_object:
                return i
            
    inverse = [where(obj,list_of_unique) for obj in object_list]
     
    return list_of_unique, inverse