[3.0.x] Fixed #31155 -- Fixed a system check for the longest choice when a named group contains only non-string values.

Regression in b6251956b69512bf230322bd7a49b629ca8455c6.

Thanks Murat Guchetl for the report.
Backport of 6f7998adc784032f4b8918ca2eea27537ea4cbbe from master

1 files changed, 2 insertions, 2 deletions

diff --git a/django/db/models/fields/__init__.py b/django/db/models/fields/__init__.py
index 37b0045ef3..e8a65c541d 100644
--- a/django/db/models/fields/__init__.py
+++ b/django/db/models/fields/__init__.py
@@ -272,10 +272,10 @@ class Field(RegisterLookupMixin):
                 ):
                     break
                 if self.max_length is not None and group_choices:
-                    choice_max_length = max(
+                    choice_max_length = max([
                         choice_max_length,
                         *(len(value) for value, _ in group_choices if isinstance(value, str)),
-                    )
+                    ])
             except (TypeError, ValueError):
                 # No groups, choices in the form [value, display]
                 value, human_name = group_name, group_choices