Fix Python tests

[yahavi]

• All tests passed. If this feature is not already covered by the tests, I added new tests.

---

PyYaml < 6.0.1 is not compatible with Cython>=3.0, which released on July 17, 2023.

This PR fixes the following stacktrace in the tests:

       Traceback (most recent call last):
        File "/opt/hostedtoolcache/Python/3.11.4/x64/lib/python3.11/site-packages/pip/_vendor/pyproject_hooks/_in_process/_in_process.py", line 353, in <module>
          main()
        File "/opt/hostedtoolcache/Python/3.11.4/x64/lib/python3.11/site-packages/pip/_vendor/pyproject_hooks/_in_process/_in_process.py", line 335, in main
          json_out['return_val'] = hook(**hook_input['kwargs'])
                                   ^^^^^^^^^^^^^^^^^^^^^^^^^^^^
        File "/opt/hostedtoolcache/Python/3.11.4/x64/lib/python3.11/site-packages/pip/_vendor/pyproject_hooks/_in_process/_in_process.py", line 118, in get_requires_for_build_wheel
          return hook(config_settings)
                 ^^^^^^^^^^^^^^^^^^^^^
        File "/tmp/pip-build-env-jxxrygqy/overlay/lib/python3.11/site-packages/setuptools/build_meta.py", line 341, in get_requires_for_build_wheel
          return self._get_build_requires(config_settings, requirements=['wheel'])
                 ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
        File "/tmp/pip-build-env-jxxrygqy/overlay/lib/python3.11/site-packages/setuptools/build_meta.py", line 323, in _get_build_requires
          self.run_setup()
        File "/tmp/pip-build-env-jxxrygqy/overlay/lib/python3.11/site-packages/setuptools/build_meta.py", line 338, in run_setup
          exec(code, locals())
        File "<string>", line 271, in <module>
        File "/tmp/pip-build-env-jxxrygqy/overlay/lib/python3.11/site-packages/setuptools/__init__.py", line 107, in setup
          return distutils.core.setup(**attrs)
                 ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
        File "/tmp/pip-build-env-jxxrygqy/overlay/lib/python3.11/site-packages/setuptools/_distutils/core.py", line 185, in setup
          return run_commands(dist)
                 ^^^^^^^^^^^^^^^^^^
        File "/tmp/pip-build-env-jxxrygqy/overlay/lib/python3.11/site-packages/setuptools/_distutils/core.py", line 201, in run_commands
          dist.run_commands()
        File "/tmp/pip-build-env-jxxrygqy/overlay/lib/python3.11/site-packages/setuptools/_distutils/dist.py", line 969, in run_commands
          self.run_command(cmd)
        File "/tmp/pip-build-env-jxxrygqy/overlay/lib/python3.11/site-packages/setuptools/dist.py", line 1234, in run_command
          super().run_command(command)
        File "/tmp/pip-build-env-jxxrygqy/overlay/lib/python3.11/site-packages/setuptools/_distutils/dist.py", line 988, in run_command
          cmd_obj.run()
        File "/tmp/pip-build-env-jxxrygqy/overlay/lib/python3.11/site-packages/setuptools/command/egg_info.py", line 314, in run
          self.find_sources()
        File "/tmp/pip-build-env-jxxrygqy/overlay/lib/python3.11/site-packages/setuptools/command/egg_info.py", line 322, in find_sources
          mm.run()
        File "/tmp/pip-build-env-jxxrygqy/overlay/lib/python3.11/site-packages/setuptools/command/egg_info.py", line 551, in run
          self.add_defaults()
        File "/tmp/pip-build-env-jxxrygqy/overlay/lib/python3.11/site-packages/setuptools/command/egg_info.py", line 589, in add_defaults
          sdist.add_defaults(self)
        File "/tmp/pip-build-env-jxxrygqy/overlay/lib/python3.11/site-packages/setuptools/command/sdist.py", line 104, in add_defaults
          super().add_defaults()
        File "/tmp/pip-build-env-jxxrygqy/overlay/lib/python3.11/site-packages/setuptools/_distutils/command/sdist.py", line 251, in add_defaults
          self._add_defaults_ext()
        File "/tmp/pip-build-env-jxxrygqy/overlay/lib/python3.11/site-packages/setuptools/_distutils/command/sdist.py", line 336, in _add_defaults_ext
          self.filelist.extend(build_ext.get_source_files())
                               ^^^^^^^^^^^^^^^^^^^^^^^^^^^^
        File "<string>", line 201, in get_source_files
        File "/tmp/pip-build-env-jxxrygqy/overlay/lib/python3.11/site-packages/setuptools/_distutils/cmd.py", line 107, in __getattr__
          raise AttributeError(attr)
      AttributeError: cython_sources
      [end of output]