Python examples are not working

[xuanhien070594]

I was trying to run the Python examples on Ubuntu 22.04, but encountered several errors as shown below.

1. Running bazel run //examples/python:c3_example produced the following error:

2. Running bazel run //examples/python:lcs_factory_example resulted in the errors shown below. I suspect this might be related to the use of std::optional in LCSFactoryOptions.

3. Running bazel run //examples/python:lcs_factory_system_example produced the same error as above.

4. Interestingly, bazel run //examples/python:c3_controller_example runs without any issues.

[xuanhien070594]

Fyi, all C++ examples are still working okay.