diff --git a/python/handwritten/common.h b/python/handwritten/common.h
new file mode 100644
index 000000000..72d2ae846
--- /dev/null
+++ b/python/handwritten/common.h
@@ -0,0 +1,31 @@
+/* ----------------------------------------------------------------------------
+
+ * GTSAM Copyright 2010, Georgia Tech Research Corporation,
+ * Atlanta, Georgia 30332-0415
+ * All Rights Reserved
+ * Authors: Frank Dellaert, et al. (see THANKS for the full author list)
+
+ * See LICENSE for the license information
+
+ * -------------------------------------------------------------------------- */
+
+/**
+ * @brief common macros used by handwritten exports of the python module
+ * @author Ellon Paiva Mendes (LAAS-CNRS)
+ **/
+
+#pragma once
+
+ /* Fix to avoid registration warnings */
+// Solution taken from https://github.com/BVLC/caffe/pull/4069/commits/673e8cfc0b8f05f9fa3ebbad7cc6202822e5d9c5 
+#define REGISTER_SHARED_PTR_TO_PYTHON(PTR) do { \
+  const boost::python::type_info info = \
+    boost::python::type_id<boost::shared_ptr<PTR > >(); \
+  const boost::python::converter::registration* reg = \
+    boost::python::converter::registry::query(info); \
+  if (reg == NULL) { \
+    boost::python::register_ptr_to_python<boost::shared_ptr<PTR > >(); \
+  } else if ((*reg).m_to_python == NULL) { \
+    boost::python::register_ptr_to_python<boost::shared_ptr<PTR > >(); \
+  } \
+} while (0)
diff --git a/python/handwritten/linear/NoiseModel.cpp b/python/handwritten/linear/NoiseModel.cpp
index 3612f7e14..00fa9d74f 100644
--- a/python/handwritten/linear/NoiseModel.cpp
+++ b/python/handwritten/linear/NoiseModel.cpp
@@ -28,6 +28,8 @@
 
 #include "gtsam/linear/NoiseModel.h"
 
+#include "python/handwritten/common.h"
+
 using namespace boost::python;
 using namespace gtsam;
 using namespace gtsam::noiseModel;
@@ -110,7 +112,7 @@ void exportNoiseModels(){
     .def("Covariance",&Gaussian::Covariance, Gaussian_Covariance_overloads())
     .staticmethod("Covariance")
   ;
-  register_ptr_to_python< boost::shared_ptr<Gaussian> >();
+  REGISTER_SHARED_PTR_TO_PYTHON(Gaussian);
   
   class_<Diagonal, boost::shared_ptr<Diagonal>, bases<Gaussian> >("Diagonal", no_init)
     .def("Sigmas",&Diagonal::Sigmas, Diagonal_Sigmas_overloads())
@@ -120,7 +122,7 @@ void exportNoiseModels(){
     .def("Precisions",&Diagonal::Precisions, Diagonal_Precisions_overloads())
     .staticmethod("Precisions")
   ;
-  register_ptr_to_python< boost::shared_ptr<Diagonal> >();
+  REGISTER_SHARED_PTR_TO_PYTHON(Diagonal);
   
   class_<Isotropic, boost::shared_ptr<Isotropic>, bases<Diagonal> >("Isotropic", no_init)
     .def("Sigma",&Isotropic::Sigma, Isotropic_Sigma_overloads())
@@ -130,12 +132,12 @@ void exportNoiseModels(){
     .def("Precision",&Isotropic::Precision, Isotropic_Precision_overloads())
     .staticmethod("Precision")
   ;
-  register_ptr_to_python< boost::shared_ptr<Isotropic> >();
+  REGISTER_SHARED_PTR_TO_PYTHON(Isotropic);
   
   class_<Unit, boost::shared_ptr<Unit>, bases<Isotropic> >("Unit", no_init)
     .def("Create",&Unit::Create)
     .staticmethod("Create")
   ;
 
-  register_ptr_to_python< boost::shared_ptr<Unit> >();
+  REGISTER_SHARED_PTR_TO_PYTHON(Unit);
 }
diff --git a/python/handwritten/navigation/ImuFactor.cpp b/python/handwritten/navigation/ImuFactor.cpp
index afc6f331d..0cf3062b5 100644
--- a/python/handwritten/navigation/ImuFactor.cpp
+++ b/python/handwritten/navigation/ImuFactor.cpp
@@ -22,6 +22,8 @@
 #include "gtsam/navigation/ImuFactor.h"
 #include "gtsam/navigation/GPSFactor.h"
 
+#include "python/handwritten/common.h"
+
 using namespace boost::python;
 using namespace gtsam;
 
@@ -78,7 +80,7 @@ void exportImuFactor() {
       .staticmethod("MakeSharedU");
 
   // NOTE(frank): https://mail.python.org/pipermail/cplusplus-sig/2016-January/017362.html
-  register_ptr_to_python< boost::shared_ptr<PreintegrationParams> >();
+  REGISTER_SHARED_PTR_TO_PYTHON(PreintegrationParams);
 
   class_<PreintegrationType>(
 #ifdef GTSAM_TANGENT_PREINTEGRATION
@@ -105,21 +107,21 @@ void exportImuFactor() {
       .def("error", &ImuFactor::error)
       .def(init<Key, Key, Key, Key, Key, const PreintegratedImuMeasurements&>())
       .def(repr(self));
-  register_ptr_to_python<boost::shared_ptr<ImuFactor>>();
+  REGISTER_SHARED_PTR_TO_PYTHON(ImuFactor);
 
   class_<ImuFactor2, bases<NonlinearFactor>, boost::shared_ptr<ImuFactor2>>("ImuFactor2")
       .def("error", &ImuFactor2::error)
       .def(init<Key, Key, Key, const PreintegratedImuMeasurements&>())
       .def(repr(self));
-  register_ptr_to_python<boost::shared_ptr<ImuFactor2>>();
+  REGISTER_SHARED_PTR_TO_PYTHON(ImuFactor2);
 
   class_<GPSFactor, bases<NonlinearFactor>, boost::shared_ptr<GPSFactor>>("GPSFactor")
       .def("error", &GPSFactor::error)
       .def(init<Key, const Point3&, noiseModel::Base::shared_ptr>());
-  register_ptr_to_python<boost::shared_ptr<GPSFactor>>();
+  REGISTER_SHARED_PTR_TO_PYTHON(GPSFactor);
 
   class_<GPSFactor2, bases<NonlinearFactor>, boost::shared_ptr<GPSFactor2>>("GPSFactor2")
       .def("error", &GPSFactor2::error)
       .def(init<Key, const Point3&, noiseModel::Base::shared_ptr>());
-  register_ptr_to_python<boost::shared_ptr<GPSFactor2>>();
+  REGISTER_SHARED_PTR_TO_PYTHON(GPSFactor2);
 }