fix: implement __repr__ method in order to avoid maximum recursion error

Author: andrey-canon

lms/djangoapps/courseware/models.py

@@ -287,6 +287,16 @@ class Meta:
 
     student_module = models.ForeignKey(StudentModule, db_index=True, db_constraint=False, on_delete=models.CASCADE)
 
+    def __repr__(self):
+        student_dict = {
+            "course_id": str(self.student_module.course_id),
+            "module_type": self.student_module.module_type,
+            "student_id": self.student_module.student_id,
+            "grade": self.grade,
+        }
+
+        return f"StudentModuleHistory<{student_dict!r}>"
+
     def __str__(self):
         return str(repr(self))