diff --git a/finder/admin/inode.py b/finder/admin/inode.py
index 044d74a20..611e20087 100644
--- a/finder/admin/inode.py
+++ b/finder/admin/inode.py
@@ -2,7 +2,6 @@
 
 from django.contrib import admin
 from django.contrib.sites.shortcuts import get_current_site
-from django.core.exceptions import ValidationError
 from django.db.models.expressions import F, Value
 from django.db.models.fields import BooleanField
 from django.db.models.functions import Lower
@@ -40,7 +39,7 @@ def get_urls(self):
 
     def get_object(self, request, object_id, from_field=None):
         site = get_current_site(request)
-        for model in InodeModel.real_models:
+        for model in InodeModel.concrete_inode_models:
             try:
                 obj = model.objects.get(id=object_id)
                 if obj.is_folder and obj.realm.site == site and obj.realm.slug == self.admin_site.name:
@@ -125,7 +124,7 @@ def get_inodes(self, request, sorting=None, **lookup):
         """
         inodes, applicable_sorting = [], []
         labels = lookup.pop('labels__in', None)
-        for inode_model in InodeModel.real_models:
+        for inode_model in InodeModel.concrete_inode_models:
             queryset = (
                 inode_model.objects.select_related('owner')
                 .filter(**lookup)
diff --git a/finder/api/views.py b/finder/api/views.py
index 530ae9999..beff19a0f 100644
--- a/finder/api/views.py
+++ b/finder/api/views.py
@@ -114,8 +114,6 @@ def list(self, request, folder_id):
         folder = FolderModel.objects.get(id=folder_id)
         request.session['finder.last_folder'] = str(folder_id)
 
-        folder.listdir(is_folder=False)
-
         return {
             'files': [{
                 'id': str(file.id),
diff --git a/finder/management/commands/reorganize_finder.py b/finder/management/commands/reorganize_finder.py
index 463c2a024..8bbe5855d 100644
--- a/finder/management/commands/reorganize_finder.py
+++ b/finder/management/commands/reorganize_finder.py
@@ -14,7 +14,7 @@ def handle(self, verbosity, *args, **options):
         self.reorganize()
 
     def reorganize(self):
-        for inode_model in InodeModel.real_models:
+        for inode_model in InodeModel.concrete_inode_models:
             if inode_model.is_folder:
                 continue
             for file in inode_model.objects.all():
diff --git a/finder/models/folder.py b/finder/models/folder.py
index a2c3b9a00..2ca737aad 100644
--- a/finder/models/folder.py
+++ b/finder/models/folder.py
@@ -85,7 +85,10 @@ def subfolders(self):
 
     @property
     def num_children(self):
-        num_children = sum(inode_model.objects.filter(parent=self).count() for inode_model in InodeModel.real_models)
+        num_children = sum(
+            inode_model.objects.filter(parent=self).count()
+            for inode_model in InodeModel.concrete_inode_models
+        )
         return num_children
 
     @cached_property
diff --git a/finder/models/inode.py b/finder/models/inode.py
index 0f6840704..b2aa59502 100644
--- a/finder/models/inode.py
+++ b/finder/models/inode.py
@@ -40,17 +40,17 @@ def _validate_accept_mime_types(new_class):
             new_class._mime_types_mapping[accept_mime_type] = new_class
 
     @property
-    def real_models(self):
+    def concrete_inode_models(self):
         """
-        Yields all real (excluding proxy models) that inherit from InodeModel.
+        Yields all concrete (excluding proxy models) that inherit from InodeModel.
         """
         yield self._inode_models['finder.FolderModel']
-        yield from self.real_file_models
+        yield from self.concrete_file_models
 
     @property
-    def real_file_models(self):
+    def concrete_file_models(self):
         """
-        Yields all real (excluding proxy models) that inherit from AbstractFileModel.
+        Yields all concrete (excluding proxy models) that inherit from AbstractFileModel.
         """
         for model in self._inode_models.values():
             if not model.is_folder and not model._meta.proxy:
@@ -74,9 +74,11 @@ class InodeManagerMixin:
     def filter_inodes(self, **lookup):
         from .folder import FolderModel
 
-        if lookup.pop('is_folder', False):
+        is_folder = lookup.pop('is_folder', None)
+        if is_folder:
             return FolderModel.objects.filter(**lookup).iterator()
-        inodes = [inode_model.objects.filter(**lookup) for inode_model in InodeModel.real_file_models]
+        concrete_models = InodeModel.concrete_file_models if is_folder is False else InodeModel.concrete_inode_models
+        inodes = [inode_model.objects.filter(**lookup) for inode_model in concrete_models]
         return chain(*inodes)
 
     def get_inode(self, **lookup):