diff --git a/.gitignore b/.gitignore
index ac83173b8..d4d4d6429 100644
--- a/.gitignore
+++ b/.gitignore
@@ -51,3 +51,5 @@ nbproject/
 .DS_Store
 .idea
 *.out
+# Python config
+stormpy/setup.cfg
diff --git a/stormpy/src/core/core.cpp b/stormpy/src/core/core.cpp
index 50b77c3f4..a217cea2c 100644
--- a/stormpy/src/core/core.cpp
+++ b/stormpy/src/core/core.cpp
@@ -42,9 +42,9 @@ std::shared_ptr<storm::models::ModelBase> buildSparseModel(storm::prism::Program
 
 void define_build(py::module& m) {
     // Build model
-    m.def("_build_model", &buildModel<double>, "Build the model", py::arg("program"), py::arg("formula"));
+    m.def("_build_model", &buildSparseModel<double>, "Build the model", py::arg("program"), py::arg("formula"), py::arg("onlyInitialRelevant") = false);
     m.def("_build_parametric_model", &buildSparseModel<storm::RationalFunction>, "Build the parametric model", py::arg("program"), py::arg("formula"), py::arg("onlyInitialRelevant") = false);
-    m.def("build_model_from_prism_program", &storm::buildSymbolicModel<double>, "Build the model", py::arg("program"), py::arg("formulas"));
+    m.def("build_model_from_prism_program", &storm::buildSparseModel<double>, "Build the model", py::arg("program"), py::arg("formulas"), py::arg("onlyInitialRelevant") = false);
     m.def("build_parametric_model_from_prism_program", &storm::buildSparseModel<storm::RationalFunction>, "Build the parametric model", py::arg("program"), py::arg("formulas"), py::arg("onlyInitialRelevant") = false);
     
 }
diff --git a/stormpy/tests/core/test_bisimulation.py b/stormpy/tests/core/test_bisimulation.py
index 7e845ffce..1a8fb8fe4 100644
--- a/stormpy/tests/core/test_bisimulation.py
+++ b/stormpy/tests/core/test_bisimulation.py
@@ -9,8 +9,7 @@ class TestBisimulation:
         assert program.model_type() == stormpy.PrismModelType.DTMC
         prop = "P=? [F \"observe0Greater1\"]"
         formulas = stormpy.parse_formulas_for_prism_program(prop, program)
-        pair = stormpy.build_model_from_prism_program(program, formulas)
-        model = pair.model()
+        model = stormpy.build_model_from_prism_program(program, formulas)
         assert model.nr_states() == 7403
         assert model.nr_transitions() == 13041
         assert model.model_type() == stormpy.ModelType.DTMC
@@ -28,8 +27,7 @@ class TestBisimulation:
         assert program.has_undefined_constants()
         prop = "P=? [F \"observe0Greater1\"]"
         formulas = stormpy.parse_formulas_for_prism_program(prop, program)
-        pair = stormpy.build_parametric_model_from_prism_program(program, formulas)
-        model = pair.model()
+        model = stormpy.build_parametric_model_from_prism_program(program, formulas)
         assert model.nr_states() == 1367
         assert model.nr_transitions() == 2027
         assert model.model_type() == stormpy.ModelType.DTMC
diff --git a/stormpy/tests/core/test_core.py b/stormpy/tests/core/test_core.py
index 421df1808..cedd750eb 100644
--- a/stormpy/tests/core/test_core.py
+++ b/stormpy/tests/core/test_core.py
@@ -8,3 +8,7 @@ class TestCore:
         import pycarl
         import pycarl.formula
         import pycarl.parse
+        pol1 = pycarl.FactorizedPolynomial(32)
+        pol2 = pycarl.FactorizedPolynomial(2)
+        rat = pycarl.FactorizedRationalFunction(pol1, pol2)
+        assert str(rat) == "16"
diff --git a/stormpy/tests/core/test_modelchecking.py b/stormpy/tests/core/test_modelchecking.py
index ba0b5f74a..d6033b1c3 100644
--- a/stormpy/tests/core/test_modelchecking.py
+++ b/stormpy/tests/core/test_modelchecking.py
@@ -28,8 +28,7 @@ class TestModelChecking:
         program = stormpy.parse_prism_program(get_example_path("pdtmc", "brp", "brp_16_2.pm"))
         prop = "P=? [F \"target\"]"
         formulas = stormpy.parse_formulas_for_prism_program(prop, program)
-        pair = stormpy.build_parametric_model_from_prism_program(program, formulas)
-        model = pair.model()
+        model = stormpy.build_parametric_model_from_prism_program(program, formulas)
         assert model.nr_states() == 613
         assert model.nr_transitions() == 803
         assert model.model_type() == stormpy.ModelType.DTMC
diff --git a/stormpy/tests/storage/test_model.py b/stormpy/tests/storage/test_model.py
index 7fc4894dc..df50c6f31 100644
--- a/stormpy/tests/storage/test_model.py
+++ b/stormpy/tests/storage/test_model.py
@@ -7,8 +7,7 @@ class TestModel:
         program = stormpy.parse_prism_program(get_example_path("dtmc", "die", "die.pm"))
         prop = "P=? [F \"one\"]"
         formulas = stormpy.parse_formulas_for_prism_program(prop, program)
-        pair = stormpy.build_model_from_prism_program(program, formulas)
-        model = pair.model()
+        model = stormpy.build_model_from_prism_program(program, formulas)
         assert model.nr_states() == 13
         assert model.nr_transitions() == 20
         assert model.model_type() == stormpy.ModelType.DTMC
@@ -22,8 +21,7 @@ class TestModel:
         assert program.has_undefined_constants()
         prop = "P=? [F \"target\"]"
         formulas = stormpy.parse_formulas_for_prism_program(prop, program)
-        pair = stormpy.build_parametric_model_from_prism_program(program, formulas)
-        model = pair.model()
+        model = stormpy.build_parametric_model_from_prism_program(program, formulas)
         assert model.nr_states() == 613
         assert model.nr_transitions() == 803
         assert model.model_type() == stormpy.ModelType.DTMC
@@ -68,7 +66,7 @@ class TestModel:
         formulas = stormpy.parse_formulas_for_prism_program("P=? [ F \"one\" ]", program)
         model = stormpy.build_model(program, formulas[0])
         labels = model.labels()
-        assert len(labels) == 2
+        assert len(labels) == 3
         assert "init" in labels
         assert "one" in labels
         assert "init" in model.labels_state(0)
@@ -87,7 +85,7 @@ class TestModel:
         formulas = stormpy.parse_formulas_for_prism_program("P=? [ F \"target\" ]", program)
         model = stormpy.build_parametric_model(program, formulas[0])
         labels = model.labels()
-        assert len(labels) == 2
+        assert len(labels) == 3
         assert "init" in labels
         assert "target" in labels
         assert "init" in model.labels_state(0)