allow completion of sbas / physics exams

generic/models.py

@@ -1518,6 +1518,12 @@ class CidUserExam(models.Model):
         else:
             return "CID" + str(self.cid_user.cid)
 
+    def complete_exam(self):   
+        # TODO add examuserstatus?
+        self.end_time = timezone.now()
+        self.completed = True
+        self.save()
+
 
 CID_GROUP_EXAMS = (
     ("SBAs", "sba_cid_user_groups"),
@@ -1729,7 +1735,10 @@ class ExamCollection(models.Model, AuthorMixin):
     )
 
     def __str__(self):
-        return f"{self.name} [{self.date}]"
+        if self.date is not None and self.date is not "":
+            return f"{self.name} [{self.date}]"
+        else:
+            return f"{self.name}"
 
     def get_absolute_url(self):
         return reverse("generic:examcollection_detail", kwargs={"pk": self.pk})