fix commas

history_tracking/models.py

@@ -0,0 +1,17 @@
+# history_tracking/models.py
+from django.db import models
+from simple_history.models import HistoricalRecords
+from .mixins import HistoricalChangeMixin
+
+
+class Park(models.Model):
+    name = models.CharField(max_length=200)
+    # ... other fields ...
+    history = HistoricalRecords()
+
+    @property
+    def _history_model(self):
+        return self.history.model
+
+
+# Apply the mixin