Sample cannot be imported from script

1. create file .py with sample script:

def get_sample():
    # Define materials
    material_Default = ba.RefractiveMaterial("Default", 0.001, 1e-05)

    # Define layers
    layer_1 = ba.Layer(material_Default)

    # Define sample
    sample = ba.MultiLayer()
    sample.addLayer(layer_1)

    return sample   

2. build BA
3. add build/py/src to PYTHONPATH
4. run GUI
5. import sample from Py --> Segmentation fault

Broken by MR !2724 (merged)

backtrace

Thread 1 "bornagain" received signal SIGSEGV, Segmentation fault.
_PyInterpreterState_GET () at ./Include/internal/pycore_pystate.h:116
116    ./Include/internal/pycore_pystate.h: No such file or directory.
(gdb) bt
#0  _PyInterpreterState_GET () at ./Include/internal/pycore_pystate.h:116
#1  get_list_state () at Objects/listobject.c:24
#2  PyList_New (size=0) at Objects/listobject.c:165
#3  0x00007ffff427d3ab in PyImport_Import (module_name=module_name@entry=0x7fffb8044030)
    at Python/import.c:1984
#4  0x00007ffff427d60a in PyImport_ImportModule (name=<optimized out>) at Python/import.c:1453
#5  0x00007ffff77f8434 in PyInterpreter::BornAgain::import(std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char> > const&) ()
   from /home/mikhail/Projects/bornagain/build/lib/_libBornAgainPyCore.so
#6  0x00007ffff77f8633 in PyInterpreter::BornAgain::importScript(std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char> > const&, std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char> > const&) ()
   from /home/mikhail/Projects/bornagain/build/lib/_libBornAgainPyCore.so
#7  0x00007ffff77f878e in PyInterpreter::BornAgain::listOfFunctions(std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char> > const&, std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char> > const&) ()
   from /home/mikhail/Projects/bornagain/build/lib/_libBornAgainPyCore.so
#8  0x00007ffff7aaa52d in IO::Py::importSample() ()