fix nested dicts, add more real life fastapi tests

tests/test_model_definition.py

@@ -95,13 +95,16 @@ def test_sqlalchemy_table_is_created(example):
 
 def test_no_pk_in_model_definition():
     with pytest.raises(ModelDefinitionError):
+
         class ExampleModel2(Model):
             __tablename__ = "example3"
             __metadata__ = metadata
             test_string = fields.String(length=250)
 
+
 def test_two_pks_in_model_definition():
     with pytest.raises(ModelDefinitionError):
+
         class ExampleModel2(Model):
             __tablename__ = "example3"
             __metadata__ = metadata
@@ -111,6 +114,7 @@ def test_two_pks_in_model_definition():
 
 def test_setting_pk_column_as_pydantic_only_in_model_definition():
     with pytest.raises(ModelDefinitionError):
+
         class ExampleModel2(Model):
             __tablename__ = "example4"
             __metadata__ = metadata
@@ -119,6 +123,7 @@ def test_setting_pk_column_as_pydantic_only_in_model_definition():
 
 def test_decimal_error_in_model_definition():
     with pytest.raises(ModelDefinitionError):
+
         class ExampleModel2(Model):
             __tablename__ = "example4"
             __metadata__ = metadata
@@ -127,6 +132,7 @@ def test_decimal_error_in_model_definition():
 
 def test_string_error_in_model_definition():
     with pytest.raises(ModelDefinitionError):
+
         class ExampleModel2(Model):
             __tablename__ = "example4"
             __metadata__ = metadata