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MareSynchronosAPI/Data/Comparer/GroupPairDtoComparer.cs

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+using MareSynchronos.API.Dto.Group;
+
+namespace MareSynchronos.API.Data.Comparer;
+
+public class GroupPairDtoComparer : IEqualityComparer<GroupPairDto>
+{
+    private static GroupPairDtoComparer _instance = new();
+
+    private GroupPairDtoComparer()
+    { }
+
+    public static GroupPairDtoComparer Instance => _instance;
+
+    public bool Equals(GroupPairDto? x, GroupPairDto? y)
+    {
+        if (x == null || y == null) return false;
+        return x.GID.Equals(y.GID, StringComparison.Ordinal) && x.UID.Equals(y.UID, StringComparison.Ordinal);
+    }
+
+    public int GetHashCode(GroupPairDto obj)
+    {
+        return HashCode.Combine(obj.Group.GID.GetHashCode(), obj.User.UID.GetHashCode());
+    }
+}