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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 datetime2et(dt):
 """ Converts a standard Python datetime to a double precision value representing the number of TDB seconds past the J2000 epoch corresponding to the input epoch. https://naif.jpl.nasa.gov/pub/naif/toolkit_docs/C/req/time.html#The%20J2000%20Epoch :param dt: A standard Python datetime :type time: datetime :return: The equivalent value in seconds past J2000, TDB. :rtype: float """

    lt = ctypes.c_double()
    if hasattr(dt, "__iter__"):
        ets    = []
        for t in dt:
            libspice.utc2et_c(stypes.stringToCharP(t.isoformat()),ctypes.byref(lt))
            checkForSpiceError(None)
            ets.append(lt.value)
        return ets
    dt = stypes.stringToCharP(dt.isoformat())
    et = ctypes.c_double()
    libspice.utc2et_c(dt, ctypes.byref(et))
    return et.value