it is simple, it is related with permission and i have fixed simply: go to your postgres(am using arch linux btw):

sudo -i -u postgres

then,

psql

then run:

GRANT ALL PRIVILEGES ON SCHEMA public TO your_django_user

and it shows output: enter image description here

and also finally run:

ALTER ROLE your_django_user WITH SUPERUSER

I HOPE NOW python manage.py migrate will work fine.