Flutter - Dart: How To Remove Duplicates From Lists

[@sveinsoermo9883]

King! Love these videos!

[@Hitogiri]

as a noob am realy learning alot from this channel

[@FlutterMentor]

Happy to know that!

[@sovrinfo]

Thanks you a lot!

[@ozahljose]

How can I do something like that in a list with two or more column?
If I have in my Firebase Db something like this:
Room Cabinet PaP Po

1005 A1 B 1
1005 A1 C 2
1005 A1 B 2
1005 A1 B 7
1005 A2 A 3
1005 A3 D 1
1007 A1 B 1
1007 A1 A 15
1007 A1 B 2
1007 A2 A 1
1007 A5 C 5
1009 A1 B 15
1009 A1 B 16
Room: [1005]
Cabinet Room 1005 = [A1, A2, A3]
PaP Cabinet A1 Room 1005 = [B, C]
PaP Cabinet A2 Room 1005 = [A]
PaP Cabinet A3 Room 1005 = [D]
Room: [1007]
Cabinet Room 1007 = [A1, A2, A5]
PaP Cabinet A1 Room 1005 = [A, B]
PaP Cabinet A2 Room 1005 = [A
]
PaP Cabinet A5 Room 1005 = [C]
Room: [1009]
Cabinet Room 1009 = [A1]
PaP Cabinet A1 Room 1005 = [B]