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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def ctypes2numpy_shared(cptr, shape):
 """Convert a ctypes pointer to a numpy array. The resulting NumPy array shares the memory with the pointer. Parameters cptr : ctypes.POINTER(mx_float) pointer to the memory region shape : tuple Shape of target `NDArray`. Returns ------- out : numpy_array A numpy array : numpy array. """

    if not isinstance(cptr, ctypes.POINTER(mx_float)):
        raise RuntimeError('expected float pointer')
    size = 1
    for s in shape:
        size *= s
    dbuffer = (mx_float * size).from_address(ctypes.addressof(cptr.contents))
    return _np.frombuffer(dbuffer, dtype=_np.float32).reshape(shape)