diff --git a/django/contrib/sessions/backends/file.py b/django/contrib/sessions/backends/file.py
index 60c10d6959..e75195f222 100644
--- a/django/contrib/sessions/backends/file.py
+++ b/django/contrib/sessions/backends/file.py
@@ -18,7 +18,7 @@ class SessionStore(SessionBase):
     Implement a file based session store.
     """
     def __init__(self, session_key=None):
-        self.storage_path = type(self)._get_storage_path()
+        self.storage_path = self._get_storage_path()
         self.file_prefix = settings.SESSION_COOKIE_NAME
         super().__init__(session_key)
 
diff --git a/tests/custom_lookups/tests.py b/tests/custom_lookups/tests.py
index 670f90f36c..5c9ee5c5ef 100644
--- a/tests/custom_lookups/tests.py
+++ b/tests/custom_lookups/tests.py
@@ -234,17 +234,14 @@ class LookupTests(TestCase):
         __exact=None is transformed to __isnull=True if a custom lookup class
         with lookup_name != 'exact' is registered as the `exact` lookup.
         """
-        class CustomExactLookup(models.Lookup):
-            lookup_name = 'somecustomlookup'
-
         field = Author._meta.get_field('birthdate')
         OldExactLookup = field.get_lookup('exact')
         author = Author.objects.create(name='author', birthdate=None)
         try:
-            type(field).register_lookup(Exactly, 'exact')
+            field.register_lookup(Exactly, 'exact')
             self.assertEqual(Author.objects.get(birthdate__exact=None), author)
         finally:
-            type(field).register_lookup(OldExactLookup, 'exact')
+            field.register_lookup(OldExactLookup, 'exact')
 
     def test_basic_lookup(self):
         a1 = Author.objects.create(name='a1', age=1)