1 files changed, 3 insertions, 0 deletions
diff --git a/models.py b/models.py
index 981d8fb..9bf5866 100644
--- a/models.py
+++ b/models.py
@@ -44,6 +44,9 @@ class Group(models.Model):
 
     slug = models.SlugField(max_length=64, unique=True, default="")
 
+    def __contains__(self, group):
+        return self.timetable == group.timetable and self.mention == group.mention and self.subgroup == group.subgroup and (self.td == group.td or self.td is None or group.td is None) and (self.tp == group.tp or self.tp is None or group.tp is None)
+
     def __str__(self):
         return self.name