use picklefield

feeds/models.py

@@ -4,6 +4,7 @@ from django.contrib.contenttypes.models import ContentType
 from django.core.cache import cache
 from django.db import models
 from django.utils import timezone
+from picklefield import PickledObjectField
 from telebot import TeleBot
 from yamlfield.fields import YAMLField
 
@@ -16,7 +17,7 @@ class Feed(models.Model):
     chat_id = models.CharField(max_length=33)
     check_interval = models.DurationField(help_text='in seconds')
     last_check = models.DateTimeField(null=True, blank=True)
-    last_id = models.JSONField(null=True, blank=True)
+    last_id = PickledObjectField(null=True, blank=True)
 
     config_type = models.ForeignKey(ContentType, on_delete=models.CASCADE)
     config_id = models.PositiveIntegerField()