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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 tipbod(ref, body, et):
 """ Return a 3x3 matrix that transforms positions in inertial coordinates to positions in body-equator-and-prime-meridian coordinates. http://naif.jpl.nasa.gov/pub/naif/toolkit_docs/C/cspice/tipbod_c.html :param ref: ID of inertial reference frame to transform from. :type ref: str :param body: ID code of body. :type body: int :param et: Epoch of transformation. :type et: float :return: Transformation (position), inertial to prime meridian. :rtype: 3x3-Element Array of floats """

    ref = stypes.stringToCharP(ref)
    body = ctypes.c_int(body)
    et = ctypes.c_double(et)
    retmatrix = stypes.emptyDoubleMatrix()
    libspice.tipbod_c(ref, body, et, retmatrix)
    return stypes.cMatrixToNumpy(retmatrix)