[3.0.x] Fixed #30931 -- Restored ability to override Model.get_FIELD_display().

Thanks Sergey Fedoseev for the implementation idea.

Regression in a68ea231012434b522ce45c513d84add516afa60.

Backport of 2d38eb0ab9f78d68c083a5b78b1eca39027b279a from master

1 files changed, 6 insertions, 2 deletions

diff --git a/django/db/models/fields/__init__.py b/django/db/models/fields/__init__.py
index d073324745..37b0045ef3 100644
--- a/django/db/models/fields/__init__.py
+++ b/django/db/models/fields/__init__.py
@@ -767,8 +767,12 @@ class Field(RegisterLookupMixin):
             if not getattr(cls, self.attname, None):
                 setattr(cls, self.attname, self.descriptor_class(self))
         if self.choices is not None:
-            setattr(cls, 'get_%s_display' % self.name,
-                    partialmethod(cls._get_FIELD_display, field=self))
+            if not hasattr(cls, 'get_%s_display' % self.name):
+                setattr(
+                    cls,
+                    'get_%s_display' % self.name,
+                    partialmethod(cls._get_FIELD_display, field=self),
+                )
 
     def get_filter_kwargs_for_object(self, obj):
         """