diff --git a/src/PYTHON/fix_python.cpp b/src/PYTHON/fix_python.cpp
index e1c0dd1fb..a7b1edfda 100644
--- a/src/PYTHON/fix_python.cpp
+++ b/src/PYTHON/fix_python.cpp
@@ -1,109 +1,110 @@
 /* ----------------------------------------------------------------------
    LAMMPS - Large-scale Atomic/Molecular Massively Parallel Simulator
    http://lammps.sandia.gov, Sandia National Laboratories
    Steve Plimpton, sjplimp@sandia.gov
 
    Copyright (2003) Sandia Corporation.  Under the terms of Contract
    DE-AC04-94AL85000 with Sandia Corporation, the U.S. Government retains
    certain rights in this software.  This software is distributed under
    the GNU General Public License.
 
    See the README file in the top-level LAMMPS directory.
 ------------------------------------------------------------------------- */
 
 /* ----------------------------------------------------------------------
    Contributing author: Axel Kohlmeyer and Richard Berger (Temple U)
 ------------------------------------------------------------------------- */
 
+#include <Python.h>
 #include <stdio.h>
 #include <string.h>
 #include "fix_python.h"
 #include "atom.h"
 #include "force.h"
 #include "update.h"
 #include "respa.h"
 #include "error.h"
 #include "python.h"
 #include "python_compat.h"
 
 using namespace LAMMPS_NS;
 using namespace FixConst;
 
 /* ---------------------------------------------------------------------- */
 
 FixPython::FixPython(LAMMPS *lmp, int narg, char **arg) :
   Fix(lmp, narg, arg)
 {
   if (narg != 6) error->all(FLERR,"Illegal fix python command");
 
   nevery = force->inumeric(FLERR,arg[3]);
   if (nevery <= 0) error->all(FLERR,"Illegal fix python command");
 
   // ensure Python interpreter is initialized
   python->init();
 
   if (strcmp(arg[4],"post_force") == 0) {
     selected_callback = POST_FORCE;
   } else if (strcmp(arg[4],"end_of_step") == 0) {
     selected_callback = END_OF_STEP;
   }
 
   // get Python function
   PyGILState_STATE gstate = PyGILState_Ensure();
 
   PyObject * pyMain = PyImport_AddModule("__main__");
 
   if (!pyMain) {
     PyGILState_Release(gstate);
     error->all(FLERR,"Could not initialize embedded Python");
   }
 
   char * fname = arg[5];
   pFunc = PyObject_GetAttrString(pyMain, fname);
 
   if (!pFunc) {
     PyGILState_Release(gstate);
     error->all(FLERR,"Could not find Python function");
   }
 
   PyGILState_Release(gstate);
 }
 
 /* ---------------------------------------------------------------------- */
 
 int FixPython::setmask()
 {
   return selected_callback;
 }
 
 /* ---------------------------------------------------------------------- */
 
 void FixPython::end_of_step()
 {
   PyGILState_STATE gstate = PyGILState_Ensure();
 
   PyObject * ptr = PY_VOID_POINTER(lmp);
   PyObject * arglist = Py_BuildValue("(O)", ptr);
 
   PyObject * result = PyEval_CallObject(pFunc, arglist);
   Py_DECREF(arglist);
 
   PyGILState_Release(gstate);
 }
 
 /* ---------------------------------------------------------------------- */
 
 void FixPython::post_force(int vflag)
 {
   if (update->ntimestep % nevery != 0) return;
 
   PyGILState_STATE gstate = PyGILState_Ensure();
 
   PyObject * ptr = PY_VOID_POINTER(lmp);
   PyObject * arglist = Py_BuildValue("(Oi)", ptr, vflag);
 
   PyObject * result = PyEval_CallObject(pFunc, arglist);
   Py_DECREF(arglist);
 
   PyGILState_Release(gstate);
 }