App: expose function getParent() to Python

src/App/DocumentObjectPy.xml

@@ -182,6 +182,15 @@ Return -1 if element visibility is not supported or element not found, 0 if invi
                           in a single group, hence only a single return value.</UserDocu>
             </Documentation>
         </Methode>
+        <Methode Name="getParent">
+            <Documentation>
+                <UserDocu>Returns the group the object is in or None if it is not part of a group.
+                          Note that an object can only be in a single group, hence only a single return
+                          value.
+                          The parent can be a simple group as with getParentGroup() or a
+                          GeoFeature group as with getParentGeoFeatureGroup().</UserDocu>
+            </Documentation>
+        </Methode>
         <Methode Name="getPathsByOutList">
             <Documentation>
                 <UserDocu>Get all paths from this object to another object following the OutList.</UserDocu>

src/App/DocumentObjectPyImp.cpp

@@ -673,6 +673,24 @@ PyObject*  DocumentObjectPy::getParentGeoFeatureGroup(PyObject *args)
     }
 }
 
+PyObject*  DocumentObjectPy::getParent(PyObject *args)
+{
+    if (!PyArg_ParseTuple(args, ""))
+        return nullptr;
+
+    try {
+        auto grp = getDocumentObjectPtr()->getFirstParent();
+        if(!grp) {
+            Py_INCREF(Py_None);
+            return Py_None;
+        }
+        return grp->getPyObject();
+    }
+    catch (const Base::Exception& e) {
+        throw Py::RuntimeError(e.what());
+    }
+}
+
 Py::Boolean DocumentObjectPy::getMustExecute() const
 {
     try {