[C++-sig] Beginner - PyObject_CallObject fails because imported module is not recognized

[BERGER Christian]

We have this simple (test) script that defines a function that we want to call via python's c api:

import pprint
import sys
counter= 0
def onInitialize(ctxt):
   global counter
   counter+=1
   pprint.pprint(sys.path)
   return counter

While executing this works fine from the python command line, when using PyObject_CallObject to execute 'onInitialize', we're getting an error that pprint was undefined: "name 'pprint' is not defined".
Moving the import statement into the function resolves the issue, but that seems wrong, and won't work for us (we want our customers to be able to provide their own implementation of onInitialize() and a bunch of other functions).
I'm assuming I'm missing something very basic, but I haven't found it...
The interesting thing is that the global variable counter is defined and increments as desired/expected when calling the function via PyObject_CallObject(.) repeatedly.

The environment is
Python 3.5.1 (64bit)
Win7


The source code is below, if anybody wants the vs solution, that can be provided.
Thanks for your help,
Christian



#include "stdafx.h"
#include "Python.h"

void hackIt()
{
    const char* const pTestScripts =
        "import pprint\n"
        "import sys\n"
        "counter= 0\n"
        "def onInitialize(ctxt):\n"
        "  global counter\n"
        "  counter+=1\n"
        "  pprint.pprint(sys.path)\n"
        "  return counter\n";

    Py_Initialize();
    PyObject* pModule = PyImport_AddModule("__main__");
    PyObject* pPyMainDict = PyModule_GetDict(pModule);
    _Py_static_string(PyId_string, "<string>");
    PyObject* pFileName = _PyUnicode_FromId(&PyId_string);
    PyObject* pScriptObject = Py_CompileStringObject(pTestScripts, pFileName, Py_file_input, NULL, 0);
    PyObject* pLocalDictionary = PyDict_New();
    if (pScriptObject)
    {
        PyObject* pResult = PyEval_EvalCode(pScriptObject, pPyMainDict, pLocalDictionary);
        if (NULL != pResult)
        {
            PyObject* pFxnObj = PyDict_GetItemString(pLocalDictionary, "onInitialize");
            long retval = -1;
            PyObject* pTuple = PyTuple_New(1);
            PyObject* pParam = PyLong_FromLong(42);

            PyTuple_SetItem(pTuple, 0, pParam); //tuple takes ownership of pParam
            PyObject* pResultObj = PyObject_CallObject(pFxnObj, pTuple);
            Py_XDECREF(pTuple);

           if (pResultObj)
            {
                printf("got a %ld\n", PyLong_AsLong(pResultObj));
                Py_DECREF(pResultObj);
            }
            else
            {
                PyObject* pPyErr = NULL;
                if (pPyErr = PyErr_Occurred())
                {
                    const char* pStr = NULL;
                    PyObject* pTypeObj = NULL;
                    PyObject* pValueObj = NULL;
                    PyObject* pWhatObj = NULL;
                    PyErr_Fetch(&pTypeObj, &pValueObj, &pWhatObj);
                    if (pValueObj)
                    {
                        if (PyBytes_Check(pValueObj))
                        {
                            printf("Error: %s\n", PyBytes_AsString(pValueObj));
                        }
                        if (PyUnicode_Check(pValueObj))
                        {
                            wchar_t buffer[1024];
                            PyUnicode_AsWideChar(pValueObj, buffer, 1024);
                            printf("Error: %S\n", buffer);
                        }
                    }
                    Py_XDECREF(pWhatObj);
                    Py_XDECREF(pValueObj);
                    Py_XDECREF(pTypeObj);
                }
            }
        }
    }
    Py_XDECREF(pLocalDictionary);
    Py_XDECREF(pScriptObject);
    Py_Finalize();
}

int _tmain(int argc, _TCHAR* argv[])
{
    hackIt();
    return 0;
}



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