[BUG] [python-nextgen] circular ImportError on spec that $ref's a spec which $ref's the prior one

Created by: j-wash-BL

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Have you provided a full/minimal spec to reproduce the issue?
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Description

When attempting the import the generated client, python throws the following stacktrace:

Traceback (most recent call last):
  File "[*project root*]\test.py", line 4, in <module>
    import geojson
  File "[*project root*]\geojson-client\geojson\__init__.py", line 21, in <module>
    from geojson.api.geo_json_api import GeoJsonApi
  File "[*project root*]\geojson-client\geojson\api\__init__.py", line 6, in <module>
    from geojson.api.geo_json_api import GeoJsonApi
  File "[*project root*]\geojson-client\geojson\api\geo_json_api.py", line 23, in <module>
    from geojson.models.geo_json_geometry import GeoJsonGeometry
  File "[*project root*]\geojson-client\geojson\models\__init__.py", line 18, in <module>
    from geojson.models.geo_json_geometry import GeoJsonGeometry
  File "[*project root*]\geojson-client\geojson\models\geo_json_geometry.py", line 22, in <module>
    from geojson.models.geometry_collection import GeometryCollection
  File "[*project root*]\geojson-client\geojson\models\geometry_collection.py", line 23, in <module>
    from geojson.models.geo_json_geometry import GeoJsonGeometry
ImportError: cannot import name 'GeoJsonGeometry' from partially initialized module 'geojson.models.geo_json_geometry' (most likely due to a circular import) ([*project root*]\geojson-client\geojson\models\geo_json_geometry.py)

A repo that can reproduce the issue can be found here

openapi-generator version

openapitools/openapi-generator-cli:latest on docker, pulled on 1/5/23

OpenAPI declaration file content or url

The spec can be found here

Generation Details

The client is generated using the following docker command in powershell:

docker run --rm -v "${PWD}/:/output" -v "${PWD}:/input" openapitools/openapi-generator-cli:latest generate `
   -g python-nextgen `
   -i /input/geojson_spec.v1.yml `
   -o /output/geojson-client `
   --additional-properties=packageName=geojson `
   --additional-properties=packageVersion=2.4.5

Steps to reproduce

Run the above command to generate client
Install the client package to my interpreter (in my case, a venv) using pip install -e geojson-client
Run any python script that attempts to run import geojson