diff --git a/src/Mod/Part/App/BSplineCurvePyImp.cpp b/src/Mod/Part/App/BSplineCurvePyImp.cpp
index f16aa93e2a..14932d2c14 100644
--- a/src/Mod/Part/App/BSplineCurvePyImp.cpp
+++ b/src/Mod/Part/App/BSplineCurvePyImp.cpp
@@ -1244,7 +1244,7 @@ PyObject* BSplineCurvePy::buildFromPolesMultsKnots(PyObject *args, PyObject *key
             Standard_Integer index = 1;
             for (Py::Sequence::iterator it = multssq.begin(); it != multssq.end() && index <= occmults.Length(); ++it) {
                 Py::Long mult(*it);
-                if (index < occmults.Length() || PyObject_Not(periodic)) {
+                if (index < occmults.Length() || !Base::asBoolean(periodic)) {
                     sum_of_mults += static_cast<int>(mult); //sum up the mults to compare them against the number of poles later
                 }
                 occmults(index++) = static_cast<int>(mult);
@@ -1254,7 +1254,7 @@ PyObject* BSplineCurvePy::buildFromPolesMultsKnots(PyObject *args, PyObject *key
             for (int i=1; i<=occmults.Length(); i++){
                 occmults.SetValue(i,1);
             }
-            if (PyObject_Not(periodic) && occmults.Length() > 0) {
+            if (!Base::asBoolean(periodic) && occmults.Length() > 0) {
                 occmults.SetValue(1, degree+1);
                 occmults.SetValue(occmults.Length(), degree+1);
                 sum_of_mults = occmults.Length()+2*degree;
@@ -1301,7 +1301,7 @@ PyObject* BSplineCurvePy::buildFromPolesMultsKnots(PyObject *args, PyObject *key
         }
         // check if the number of poles matches the sum of mults
         if ((Base::asBoolean(periodic) && sum_of_mults != number_of_poles) ||
-                ((PyObject_Not(periodic) ? true : false) && sum_of_mults - degree -1 != number_of_poles)) {
+            (!Base::asBoolean(periodic) && sum_of_mults - degree -1 != number_of_poles)) {
             Standard_Failure::Raise("number of poles and sum of mults mismatch");
             return(nullptr);
         }
diff --git a/src/Mod/Part/App/BSplineSurfacePyImp.cpp b/src/Mod/Part/App/BSplineSurfacePyImp.cpp
index 05e50cdbec..2f5eaf8b5f 100644
--- a/src/Mod/Part/App/BSplineSurfacePyImp.cpp
+++ b/src/Mod/Part/App/BSplineSurfacePyImp.cpp
@@ -1412,7 +1412,7 @@ PyObject* BSplineSurfacePy::buildFromPolesMultsKnots(PyObject *args, PyObject *k
         Standard_Integer index = 1;
         for (Py::Sequence::iterator it = umultssq.begin(); it != umultssq.end() && index <= occumults.Length(); ++it) {
             Py::Long mult(*it);
-            if (index < occumults.Length() || PyObject_Not(uperiodic)) {
+            if (index < occumults.Length() || !Base::asBoolean(uperiodic)) {
                 sum_of_umults += static_cast<int>(mult); //sum up the mults to compare them against the number of poles later
             }
             occumults(index++) = static_cast<int>(mult);
@@ -1421,7 +1421,7 @@ PyObject* BSplineSurfacePy::buildFromPolesMultsKnots(PyObject *args, PyObject *k
         index = 1;
         for (Py::Sequence::iterator it = vmultssq.begin(); it != vmultssq.end() && index <= occvmults.Length(); ++it) {
             Py::Long mult(*it);
-            if (index < occvmults.Length() || PyObject_Not(vperiodic)) {
+            if (index < occvmults.Length() || !Base::asBoolean(vperiodic)) {
                 sum_of_vmults += static_cast<int>(mult); //sum up the mults to compare them against the number of poles later
             }
             occvmults(index++) = static_cast<int>(mult);
@@ -1454,9 +1454,9 @@ PyObject* BSplineSurfacePy::buildFromPolesMultsKnots(PyObject *args, PyObject *k
             }
         }
         if ((Base::asBoolean(uperiodic) && sum_of_umults != lu) ||
-            ((PyObject_Not(uperiodic) ? true : false) && sum_of_umults - udegree -1 != lu) ||
+            (!Base::asBoolean(uperiodic) && sum_of_umults - udegree -1 != lu) ||
             (Base::asBoolean(vperiodic) && sum_of_vmults != lv) ||
-            ((PyObject_Not(vperiodic) ? true : false) && sum_of_vmults - vdegree -1 != lv)) {
+            (!Base::asBoolean(vperiodic) && sum_of_vmults - vdegree -1 != lv)) {
             Standard_Failure::Raise("number of poles and sum of mults mismatch");
         }
         // check multiplicity of inner knots
diff --git a/src/Mod/Part/App/Geom2d/BSplineCurve2dPyImp.cpp b/src/Mod/Part/App/Geom2d/BSplineCurve2dPyImp.cpp
index c21b2ea909..e1c843b911 100644
--- a/src/Mod/Part/App/Geom2d/BSplineCurve2dPyImp.cpp
+++ b/src/Mod/Part/App/Geom2d/BSplineCurve2dPyImp.cpp
@@ -1145,7 +1145,7 @@ PyObject* BSplineCurve2dPy::buildFromPolesMultsKnots(PyObject *args, PyObject *k
             Standard_Integer index = 1;
             for (Py::Sequence::iterator it = multssq.begin(); it != multssq.end() && index <= occmults.Length(); ++it) {
                 Py::Long mult(*it);
-                if (index < occmults.Length() || PyObject_Not(periodic)) {
+                if (index < occmults.Length() || !Base::asBoolean(periodic)) {
                     sum_of_mults += (int)mult; //sum up the mults to compare them against the number of poles later
                 }
                 occmults(index++) = mult;
@@ -1155,7 +1155,7 @@ PyObject* BSplineCurve2dPy::buildFromPolesMultsKnots(PyObject *args, PyObject *k
             for (int i=1; i<=occmults.Length(); i++){
                 occmults.SetValue(i,1);
             }
-            if (PyObject_Not(periodic) && occmults.Length() > 0) {
+            if (!Base::asBoolean(periodic) && occmults.Length() > 0) {
                 occmults.SetValue(1, degree+1);
                 occmults.SetValue(occmults.Length(), degree+1);
                 sum_of_mults = occmults.Length()+2*degree;
@@ -1194,7 +1194,7 @@ PyObject* BSplineCurve2dPy::buildFromPolesMultsKnots(PyObject *args, PyObject *k
         }
         // check if the number of poles matches the sum of mults
         if (((Base::asBoolean(periodic)) && sum_of_mults != number_of_poles) ||
-                ((PyObject_Not(periodic) ? true : false) && sum_of_mults - degree -1 != number_of_poles)) {
+             (!Base::asBoolean(periodic) && sum_of_mults - degree -1 != number_of_poles)) {
             Standard_Failure::Raise("number of poles and sum of mults mismatch");
             return(nullptr);
         }