Avoid memory leakage in smart pointers wrapper

modules/python/src2/cv2.cpp

@@ -1274,14 +1274,16 @@ PyObject* pyopencv_from(const Moments& m)
 template<typename T>
 PyObject* pyopencv_from(const cv::Ptr<T>& p)
 {
-    if (!p) return Py_None;
+    if (!p)
+        Py_RETURN_NONE;
     return pyopencv_from(*p);
 }
 
 template <typename T>
 bool pyopencv_to(PyObject *o, Ptr<T>& p, const char *name)
 {
-    if (!o || o == Py_None) return true;
+    if (!o || o == Py_None)
+        return true;
     p = makePtr<T>();
     return pyopencv_to(o, *p, name);
 }