Strange behavior with ternary operator

I noticed strange behavior while trying to use ternary operator with `boost::python::dict` and `list`.
I'm trying to do something like this
```cpp
using py = boost::python;

py::dict globals;
py::dict dict;
py::list list;
bool condition = true;
globals["mol"] = condition ? dict : list;
py::exec("print(type(mol))", globals);
```

What I expected: `` or ``
What I got: ``

Is it expected behavior? Then can someone explain me why?
Or this is a bug?

重現提供的 C++ Boost.Python 程式碼片段，並檢查兩個條件值所產生的 Python 型別。判斷對全域變數進行三元指派是預期行為還是 Boost.Python 的 bug；完成標準是記錄說明，或找出需要修正的相關行為。

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