Fixed #25175 -- Renamed the postgresql_psycopg2 database backend to postgresql.

django/db/backends/postgresql/features.py

@@ -0,0 +1,30 @@
+from django.db.backends.base.features import BaseDatabaseFeatures
+from django.db.utils import InterfaceError
+
+
+class DatabaseFeatures(BaseDatabaseFeatures):
+    allows_group_by_selected_pks = True
+    can_return_id_from_insert = True
+    has_real_datatype = True
+    has_native_uuid_field = True
+    has_native_duration_field = True
+    driver_supports_timedelta_args = True
+    can_defer_constraint_checks = True
+    has_select_for_update = True
+    has_select_for_update_nowait = True
+    has_bulk_insert = True
+    uses_savepoints = True
+    can_release_savepoints = True
+    supports_tablespaces = True
+    supports_transactions = True
+    can_introspect_autofield = True
+    can_introspect_ip_address_field = True
+    can_introspect_small_integer_field = True
+    can_distinct_on_fields = True
+    can_rollback_ddl = True
+    supports_combined_alters = True
+    nulls_order_largest = True
+    closed_cursor_error_class = InterfaceError
+    has_case_insensitive_like = False
+    requires_sqlparse_for_splitting = False
+    greatest_least_ignores_nulls = True