Created by: jacquesqiao

Pybind11 has an auto type conversion feature. It will convert any sequence type as std::vector (or std::list) into Python list type, so the self-defined methods are lost.

https://github.com/pybind/pybind11/pull/445

It provides a macro PYBIND11_MAKE_OPAQUE to disable this feature. http://pybind11.readthedocs.io/en/stable/advanced/cast/stl.html#making-opaque-types