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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 utc2et(utcstr):
 """ Convert an input time from Calendar or Julian Date format, UTC, to ephemeris seconds past J2000. http://naif.jpl.nasa.gov/pub/naif/toolkit_docs/C/cspice/utc2et_c.html :param utcstr: Input time string, UTC. :type utcstr: str :return: Output epoch, ephemeris seconds past J2000. :rtype: float """

    utcstr = stypes.stringToCharP(utcstr)
    et = ctypes.c_double()
    libspice.utc2et_c(utcstr, ctypes.byref(et))
    return et.value