Get the GIL before raising an exception

git-svn-id: https://svn.wxwidgets.org/svn/wx/wxWidgets/trunk@26922 c3d73ce0-8a6f-49c7-b76d-6d57e0e08775

wxPython/src/_evthandler.i

@@ -53,7 +53,8 @@ public:
                                  &wxPyCallback::EventThunker);
             }
             else {
-                PyErr_SetString(PyExc_TypeError, "Expected callable object or None.");
+                wxPyBLOCK_THREADS(
+                    PyErr_SetString(PyExc_TypeError, "Expected callable object or None."));
             }
         }