hide set_up() (now _set_up()), since it's implicitly called

lib/stormpy/__init__.py

@@ -4,7 +4,7 @@ from . import storage
 from .storage import *
 from .version import __version__
 
-core.set_up("")
+core._set_up("")
 
 def build_model(program, formulae):
     intermediate = core._build_model(program, formulae)

src/core/core.cpp

@@ -2,7 +2,7 @@
 
 void define_core(py::module& m) {
     // Init
-    m.def("set_up", [](std::string const& args) {
+    m.def("_set_up", [](std::string const& args) {
             storm::utility::setUp();
             storm::settings::initializeAll("StoRM-Py", "stormpy");
             storm::settings::SettingsManager::manager().setFromString(args);