OneOf with list isn't producing Python valid syntax

[jsciame]

Describe the bug
I have an open api schema that I'm attempting to generate a client for. The open api schema has a oneOf block where it has a mix of type is a string or a list of strings. When I create a client with the oneOf, I get invalid syntax Python.

"message": { "oneOf": [ { "type": "string" }, { "type": "array", "items": { "type": "string" } } ]

`def to_dict(self) -> Dict[str, Any]:
status_code = self.status_code
error = self.error

    elif isinstance(self.message, list):
        message = self.message

    else:
        message = self.message

    path = self.path
    timestamp = self.timestamp

    field_dict: Dict[str, Any] = {}
    field_dict.update(self.additional_properties)
    field_dict.update({
        "statusCode": status_code,
        "error": error,
        "message": message,
        "path": path,
        "timestamp": timestamp,
    })

    return field_dict`

To Reproduce
Steps to reproduce the behavior:
openapi-python-client generate --path openapi/openapi.json
Updating gcs_delivery_api_client
Error(s) encountered while generating, client was not created

black failed
reformatted gcs_delivery_api_client/init.py
reformatted gcs_delivery_api_client/api/init.py
reformatted gcs_delivery_api_client/models/deliverable_details_dto_residence.py
reformatted gcs_delivery_api_client/api/ping/ping.py
reformatted gcs_delivery_api_client/models/deliverable_metadata_additional_audio_code.py
reformatted gcs_delivery_api_client/models/deliverable_dto_latest_delivery_status.py
reformatted gcs_delivery_api_client/client.py
reformatted gcs_delivery_api_client/api/health/health_controller_check.py
reformatted gcs_delivery_api_client/models/deliverable_metadata_captions_timecode_type.py
reformatted gcs_delivery_api_client/api/status/status_controller_get_status.py
reformatted gcs_delivery_api_client/models/deliverable_details_dto.py
reformatted gcs_delivery_api_client/models/deliverable_metadata_captions_video_format.py
reformatted gcs_delivery_api_client/models/deliverable_metadata_details_dto_residence.py
reformatted gcs_delivery_api_client/models/deliverable_metadata_audio_track_code.py
reformatted gcs_delivery_api_client/models/deliverable_metadata_additional_audio_language.py
reformatted gcs_delivery_api_client/models/aws_s3_upload_delivery_method_details_dto.py
reformatted gcs_delivery_api_client/models/deliverable_metadata_dto_cut_type.py
reformatted gcs_delivery_api_client/models/deliverable_metadata_dto_credit_status.py
reformatted gcs_delivery_api_client/models/deliverable_metadata_dto_uhd.py
reformatted gcs_delivery_api_client/models/deliverable_metadata_dto_material_type.py
reformatted gcs_delivery_api_client/models/deliverable_metadata_dto_timecode_type.py
reformatted gcs_delivery_api_client/models/deliverable_metadata_audio_track_language.py
reformatted gcs_delivery_api_client/models/deliverable_metadata_additional_audio.py
reformatted gcs_delivery_api_client/models/deliverable_metadata_dto_video_format.py
reformatted gcs_delivery_api_client/models/deliverable_metadata_captions_language.py
error: cannot format gcs_delivery_api_client/models/error_response_bad_request.py: Cannot parse: 32:8: elif isinstance(self.message, list):
reformatted gcs_delivery_api_client/models/deliverable_metadata_audio_track.py
reformatted gcs_delivery_api_client/models/deliverable_metadata_details_dto.py
reformatted gcs_delivery_api_client/models/deliverable_metadata_dto_language.py
reformatted gcs_delivery_api_client/api/projects/get_projects.py
reformatted gcs_delivery_api_client/models/delivery_replacement_dto.py
reformatted gcs_delivery_api_client/models/error_response_forbidden_message.py
reformatted gcs_delivery_api_client/models/deliverable_dto.py
reformatted gcs_delivery_api_client/models/error_response_internal_server_error_message.py
reformatted gcs_delivery_api_client/api/deliveries/initiate_deliveries.py
reformatted gcs_delivery_api_client/models/error_response_not_found_message.py
reformatted gcs_delivery_api_client/models/deliverable_metadata_captions.py
reformatted gcs_delivery_api_client/models/delivery_initiation_request_dto.py
reformatted gcs_delivery_api_client/models/error_response_service_unavailable.py
reformatted gcs_delivery_api_client/models/deliverable_metadata_dto.py
reformatted gcs_delivery_api_client/models/error_response_forbidden.py
reformatted gcs_delivery_api_client/models/delivery_initiation_request_entry_dto.py
reformatted gcs_delivery_api_client/models/error_response_internal_server_error.py
reformatted gcs_delivery_api_client/models/deliverable_metadata_segment.py
reformatted gcs_delivery_api_client/models/error_response_not_found.py
reformatted gcs_delivery_api_client/api/deliverables/get_deliverables_by_project.py
reformatted gcs_delivery_api_client/models/get_deliverables_by_project_statuses_item.py
reformatted gcs_delivery_api_client/models/error_response_service_unavailable_message.py
reformatted gcs_delivery_api_client/models/error_response_unauthorized_message.py
reformatted gcs_delivery_api_client/models/health_controller_check_response_200_info.py
reformatted gcs_delivery_api_client/models/health_controller_check_response_200_details_additional_property.py
reformatted gcs_delivery_api_client/models/health_controller_check_response_200_details.py
reformatted gcs_delivery_api_client/models/get_deliverables_response_dto.py
reformatted gcs_delivery_api_client/models/health_controller_check_response_200_info_additional_property.py
reformatted gcs_delivery_api_client/models/get_projects_response_dto.py
reformatted gcs_delivery_api_client/models/initiate_delivery_for_aws_s3_upload_response_dto_status.py
reformatted gcs_delivery_api_client/models/health_controller_check_response_200_error_additional_property.py
reformatted gcs_delivery_api_client/models/health_controller_check_response_503_details.py
reformatted gcs_delivery_api_client/models/initiate_delivery_for_signiant_flight_cli_response_dto_status.py
reformatted gcs_delivery_api_client/models/initiated_delivery_result_dto_status.py
reformatted gcs_delivery_api_client/models/health_controller_check_response_200_error.py
reformatted gcs_delivery_api_client/models/error_response_unauthorized.py
reformatted gcs_delivery_api_client/models/replacement_category_name.py
reformatted gcs_delivery_api_client/models/requested_delivery_method_dto_method.py
reformatted gcs_delivery_api_client/models/health_controller_check_response_503_details_additional_property.py
reformatted gcs_delivery_api_client/models/status_check_result_status.py
reformatted gcs_delivery_api_client/models/health_controller_check_response_503_error.py
reformatted gcs_delivery_api_client/models/health_controller_check_response_503_info.py
reformatted gcs_delivery_api_client/models/health_controller_check_response_503_error_additional_property.py
reformatted gcs_delivery_api_client/types.py
reformatted gcs_delivery_api_client/models/health_controller_check_response_503_info_additional_property.py
reformatted gcs_delivery_api_client/models/project_dto.py
reformatted gcs_delivery_api_client/models/health_controller_check_response_200.py
reformatted gcs_delivery_api_client/models/status_check_result.py
reformatted gcs_delivery_api_client/models/timecode_slot.py
reformatted gcs_delivery_api_client/models/health_controller_check_response_503.py
reformatted gcs_delivery_api_client/models/signiant_flight_delivery_method_details_dto.py
reformatted gcs_delivery_api_client/models/requested_delivery_method_dto.py
reformatted gcs_delivery_api_client/models/initiate_delivery_for_aws_s3_upload_response_dto.py
reformatted gcs_delivery_api_client/models/initiate_delivery_for_signiant_flight_cli_response_dto.py
reformatted gcs_delivery_api_client/models/initiated_delivery_result_dto.py

Oh no! 💥 💔 💥
80 files reformatted, 7 files left unchanged, 1 file failed to reformat.

Expected behavior
Generate a proper open api python code. you can see the existing code as an elif instead of an if elif or an if else.

Desktop (please complete the following information):

• OS: macOS 10.15.7
• Python Version: 3.9.1
• openapi-python-client version 0.11.1

[dbanty]

I believe this is a duplicate of #603 but please re-open if I'm wrong.