Way to remove surfaces with the same name?

Question

I am trying to find a way to remove repetitive surfaces. I have a list containing "Scenes" which is just a scene and its name: eg

[(<Surface(1600x800x32 SW)>, 'Level1_surf'), (<Surface(1600x800x32 SW)>, 'Background2_surf'), (<Surface(1600x800x32 SW)>, 'Garden_surf')]

essentially, for some reason even when i call scene_check(self) which does the following:

def scene_check(self):
    list_of_all_names = []
    for scene in self.all_scenes:
        list_of_all_names.append(scene[1])
    list_of_unique_names= []
    for scene in self.all_scenes:
        if scene[1] not in list_of_unique_names:
            list_of_unique_names.append(scene[1])
    new_list = []
    for scene in self.all_scenes:
        if scene[1] in list_of_unique_names:
            new_list.append(scene)
    self.all_scenes = new_list

(this is meant to remove any duplicate surfaces, such as if two have "Level1_surf" it will remove the second one, however, this is not happening, and my list ends up as this over time):

DEBUG: all_scenes: [(<Surface(1600x800x32 SW)>, 'Background2_surf'), (<Surface(1600x800x32 SW)>, 'Garden_surf'), (<Surface(1600x800x32 SW)>, 'Level1_surf'), (<Surface(1600x800x32 SW)>, 'Background2_surf'), (<Surface(1600x800x32 SW)>, 'Garden_surf'), (<Surface(1600x800x32 SW)>, 'Level1_surf'), (<Surface(1600x800x32 SW)>, 'Background2_surf'), (<Surface(1600x800x32 SW)>, 'Garden_surf'), (<Surface(1600x800x32 SW)>, 'Level1_surf')]

can anyone either explain why my method doesn't work or provide the proper way to do this? Thank you.