We have a memory-view object represented with the following structure:

typedef struct {
    PyObject_VAR_HEAD
    _PyManagedBufferObject *mbuf; /* managed buffer */
    Py_hash_t hash;               /* hash value for read-only views */
    int flags;                    /* state flags */
    Py_ssize_t exports;           /* number of buffer re-exports */
    Py_buffer view;               /* private copy of the exporter's view */
    PyObject *weakreflist;
    Py_ssize_t ob_array[1];       /* shape, strides, suboffsets */
} PyMemoryViewObject;

It would be good to have the implementation for PyObject_GetMemoryView which returns a memory-view object as was originally intended in PEP 3118 i.e :

PyObject *PyObject_GetMemoryView(PyObject *obj)