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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 gfevnt(udstep, udrefn, gquant, qnpars, lenvals, qpnams, qcpars, qdpars, qipars, qlpars, op, refval, tol, adjust, rpt, udrepi, udrepu, udrepf, nintvls, bail, udbail, cnfine, result=None):
 """ Determine time intervals when a specified geometric quantity satisfies a specified mathematical condition. http://naif.jpl.nasa.gov/pub/naif/toolkit_docs/C/cspice/gfevnt_c.html :param udstep: Name of the routine that computes and returns a :type udstep: spiceypy.utils.callbacks.UDSTEP :param udrefn: Name of the routine that computes a refined time :type udrefn: spiceypy.utils.callbacks.UDREFN :param gquant: Type of geometric quantity :type gquant: str :param qnpars: Number of quantity definition parameters :type qnpars: int :param lenvals: Length of strings in qpnams and qcpars :type lenvals: int :param qpnams: Names of quantity definition parameters :type qpnams: List :param qcpars: Array of character quantity definition parameters :type qcpars: List :param qdpars: Array of double precision quantity definition :type qdpars: N-Element Array of floats :param qipars: Array of integer quantity definition parameters :type qipars: N-Element Array of str :param qlpars: Array of logical quantity definition parameters :type qlpars: N-Element Array of int :param op: Operator that either looks for an extreme value :type op: str :param refval: Reference value :type refval: float :param tol: Convergence tolerance in seconds :type tol: float :param adjust: Absolute extremum adjustment value :type adjust: float :param rpt: Progress reporter on TRUE or off FALSE :type rpt: int :param udrepi: Function that initializes progress reporting :type udrepi: spiceypy.utils.callbacks.UDREPI :param udrepu: Function that updates the progress report :type udrepu: spiceypy.utils.callbacks.UDREPU :param udrepf: Function that finalizes progress reporting :type udrepf: spiceypy.utils.callbacks.UDREPF :param nintvls: Workspace window interval count :type nintvls: int :param bail: Logical indicating program interrupt monitoring :type bail: int :param udbail: Name of a routine that signals a program interrupt :type udbail: spiceypy.utils.callbacks.UDBAIL :param cnfine: SPICE window to which the search is restricted :type cnfine: spiceypy.utils.support_types.SpiceCell :param result: Optional SPICE window containing results :type result: spiceypy.utils.support_types.SpiceCell """

    assert isinstance(cnfine, stypes.SpiceCell)
    assert cnfine.is_double()
    if result is None:
        result = stypes.SPICEDOUBLE_CELL(2000)
    else:
        assert isinstance(result, stypes.SpiceCell)
        assert result.is_double()
    gquant  = stypes.stringToCharP(gquant)
    qnpars  = ctypes.c_int(qnpars)
    lenvals = ctypes.c_int(lenvals)
    qpnams  = stypes.listToCharArrayPtr(qpnams, xLen=lenvals, yLen=qnpars)
    qcpars  = stypes.listToCharArrayPtr(qcpars, xLen=lenvals, yLen=qnpars)
    qdpars  = stypes.toDoubleVector(qdpars)
    qipars  = stypes.toIntVector(qipars)
    qlpars  = stypes.toIntVector(qlpars)
    op      = stypes.stringToCharP(op)
    refval  = ctypes.c_double(refval)
    tol     = ctypes.c_double(tol)
    adjust  = ctypes.c_double(adjust)
    rpt     = ctypes.c_int(rpt)
    nintvls = ctypes.c_int(nintvls)
    bail    = ctypes.c_int(bail)
    libspice.gfevnt_c(udstep, udrefn, gquant, qnpars, lenvals, qpnams, qcpars,
                      qdpars, qipars, qlpars, op, refval, tol,
                      adjust, rpt, udrepi, udrepu, udrepf, nintvls, bail,
                      udbail, ctypes.byref(cnfine), ctypes.byref(result))
    return result