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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 lspcn(body, et, abcorr):
 """ Compute L_s, the planetocentric longitude of the sun, as seen from a specified body. http://naif.jpl.nasa.gov/pub/naif/toolkit_docs/C/cspice/lspcn_c.html :param body: Name of central body. :type body: str :param et: Epoch in seconds past J2000 TDB. :type et: float :param abcorr: Aberration correction. :type abcorr: str :return: planetocentric longitude of the sun :rtype: float """

    body = stypes.stringToCharP(body)
    et = ctypes.c_double(et)
    abcorr = stypes.stringToCharP(abcorr)
    return libspice.lspcn_c(body, et, abcorr)