Accessing dynamic array of struct in Python using ctypes

Related to this: python ctypes array of structs

I have a struct of struct in C. I am creating one of them dynamically and would like to access it in python using ctypes.

Below is an example:

foo.c

#include <stdlib.h>
#include <stdio.h>
#include <string.h>
#include "foo.h"

MyStruct * ms;

void setIt()
{
        ms = (MyStruct *)(calloc(1, sizeof(MyStruct)));
        ms->a = 10;
        ms->b = 99.99;
        ms->dynamic_p = (Point *)(calloc(2, sizeof(Point)));
        int i;
        for(i=0; i<5; i++)
        {
                ms->p[i].x = i*5;
                ms->p[i].y = i*10;
        }       
        for(i=0; i<2; i++)
        {
                ms->dynamic_p[i].x = i+88;
                ms->dynamic_p[i].y = i+88;
        }
}

MyStruct * retIt()
{
        return ms;
}

void main()
{
        setIt();
        printf("a: %d\n", ms->a);
        printf("p[0].x: %d\n", ms->p[3].x);
        printf("dynamic_p[0].y: %d\n", ms->dynamic_p[0].y);
}

foo.h

#ifndef FOO_H
#define FOO_H

typedef struct POINT
{
        int x;
        int y;
}Point;

typedef struct MYSTRUCT
{
        int a;
        double b;
        Point p[5];
        Point * dynamic_p;
}MyStruct;

void setIt();

MyStruct * retIt();

#endif

After compiling with gcc -shared -o test.so -fPIC foo.c

test.py

import ctypes
class Point(ctypes.Structure):
 _fields_ = [('x', ctypes.c_int), ('y', ctypes.c_int)]


class MyStruct(ctypes.Structure):
 _fields_ = [('a', ctypes.c_int), ('b', ctypes.c_double), ('p', Point*5), ('dynamic_p', ctypes.POINTER(Point))]


simulator = ctypes.cdll.LoadLibrary('your/path/to/test.so')

simulator.retIt.restype = ctypes.POINTER(MyStruct)
simulator.setIt()
pyMS = simulator.retIt()

pyMS.contents.dynamic_p[0].x

I can access the p array without a problem.

The last line returns a segmentation fault. I understand that I must be accessing an illegal part of memory. But I have tries all types of combination and cannot get it to work.

Really would really appreciate any light on the subject.

EDIT: Posted the wrong python code last and forgot the dynamic_p feild

Cheers