Clean Way to Convert Python 3 Unicode to std::string

I wrap a lot of C++ using the Python 2 API (I can't use things like swig or boost.python for various technical reasons). When I have to pass a string (usually a path, always ASCII) into C/C++, I use something like this: ``` std::string file_name = PyString_AsString(py_file_name); if (PyErr_Occurred()) return NULL; ``` Now I'm considering updating to Python 3, where `PyString_*` methods don't exist. I found one solution that says I should do something like this: ``` PyObject* bytes = PyUnicode_AsUTF8String(py_file_name); std::string file_name = PyBytes_AsString(bytes); if (PyErr_Occurred()) return NULL; Py_DECREF(bytes); ``` However this is twice as many lines and seems a bit ugly (not to mention that it could introduce a memory leak if I forget the last line). The other option is to redefine the python functions to operate on `bytes` objects, and to call them like this ``` def some_function(path_name): _some_function(path_name.encode('utf8')) ``` This isn't terrible, but it does require a python-side wrapper for each function. Is there some cleaner way to deal with this?