BUG: Fix the OWNDATA flags of the array

cython_wrapper.pyx

@@ -40,4 +40,10 @@ def py_compute(int size):
     # new Python object pointing to the existing data
     # new Python object pointing to the existing data
     ndarray = np.PyArray_SimpleNewFromData(1, shape,
     ndarray = np.PyArray_SimpleNewFromData(1, shape,
                     np.NPY_INT, <void *> array)
                     np.NPY_INT, <void *> array)
+
+    # Tell Python that it can deallocate the memory when the ndarray
+    # object gets garbage collected
+    # As the OWNDATA flag of an array is read-only in Python, we need to
+    # call the C function PyArray_UpdateFlags
+    np.PyArray_UpdateFlags(ndarray, ndarray.flags.num | np.NPY_OWNDATA)
     return ndarray
     return ndarray