Remove more python2 stuff

InvenTree/part/admin.py

@@ -1,6 +1,3 @@
-# -*- coding: utf-8 -*-
-from __future__ import unicode_literals
-
 from django.contrib import admin
 
 from import_export.admin import ImportExportModelAdmin

InvenTree/part/apps.py

@@ -1,5 +1,3 @@
-from __future__ import unicode_literals
-
 import logging
 
 from django.db.utils import OperationalError, ProgrammingError

InvenTree/part/tasks.py

@@ -1,6 +1,3 @@
-# -*- coding: utf-8 -*-
-from __future__ import unicode_literals
-
 import logging
 
 from django.utils.translation import gettext_lazy as _

InvenTree/part/test_api.py

@@ -1,6 +1,3 @@
-# -*- coding: utf-8 -*-
-from __future__ import unicode_literals
-
 import PIL
 
 from django.urls import reverse

InvenTree/part/test_bom_item.py

@@ -1,6 +1,4 @@
-# -*- coding: utf-8 -*-
 
-from __future__ import unicode_literals
 from django.db import transaction
 
 from django.test import TestCase

InvenTree/part/test_part.py

@@ -1,8 +1,5 @@
 # Tests for the Part model
 
-# -*- coding: utf-8 -*-
-
-from __future__ import unicode_literals
 from allauth.account.models import EmailAddress
 
 from django.contrib.auth import get_user_model