Add sqlmodel to gel-orm generator.

This is similar to SQLAlchemy model generator, but the results are
SQLModels instead.

gel/_testbase.py

@@ -40,6 +40,7 @@
 from gel import blocking_client
 from gel.orm.introspection import get_schema_json, GelORMWarning
 from gel.orm.sqla import ModelGenerator as SQLAModGen
+from gel.orm.sqlmodel import ModelGenerator as SQLModGen
 from gel.orm.django.generator import ModelGenerator as DjangoModGen
 
 
@@ -694,6 +695,26 @@ def get_dsn_for_sqla(cls):
         return dsn
 
 
+class SQLModelTestCase(ORMTestCase):
+    @classmethod
+    def setupORM(cls):
+        gen = SQLModGen(
+            outdir=os.path.join(cls.tmpormdir.name, cls.MODEL_PACKAGE),
+            basemodule=cls.MODEL_PACKAGE,
+        )
+        gen.render_models(cls.spec)
+
+    @classmethod
+    def get_dsn_for_sqla(cls):
+        cargs = cls.get_connect_args(database=cls.get_database_name())
+        dsn = (
+            f'postgresql://{cargs["user"]}:{cargs["password"]}'
+            f'@{cargs["host"]}:{cargs["port"]}/{cargs["database"]}'
+        )
+
+        return dsn
+
+
 APPS_PY = '''\
 from django.apps import AppConfig
 

gel/orm/cli.py

@@ -25,6 +25,7 @@
 from gel.codegen.generator import _get_conn_args
 from .introspection import get_schema_json, GelORMWarning
 from .sqla import ModelGenerator as SQLAModGen
+from .sqlmodel import ModelGenerator as SQLModGen
 from .django.generator import ModelGenerator as DjangoModGen
 
 
@@ -41,7 +42,7 @@ def error(self, message):
 )
 parser.add_argument(
     "orm",
-    choices=['sqlalchemy', 'django'],
+    choices=['sqlalchemy', 'sqlmodel', 'django'],
     help="Pick which ORM to generate models for.",
 )
 parser.add_argument("--dsn")
@@ -97,6 +98,16 @@ def generate_models(args, spec):
             )
             gen.render_models(spec)
 
+        case 'sqlmodel':
+            if args.mod is None:
+                parser.error('sqlmodel requires to specify --mod')
+
+            gen = SQLModGen(
+                outdir=args.out,
+                basemodule=args.mod,
+            )
+            gen.render_models(spec)
+
         case 'django':
             gen = DjangoModGen(
                 out=args.out,