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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 from_dynacRepr(cls, pynacRepr):
 """ Construct a ``AccGap`` instance from the Pynac lattice element """

        pynacList = pynacRepr[1][0]

        L = float(pynacList[3])
        TTF = float(pynacList[4])
        TTFprime = float(pynacList[5])
        TTFprimeprime = float(pynacList[13])
        EField = float(pynacList[10])
        phase = float(pynacList[11])
        F = float(pynacList[14])
        atten = float(pynacList[15])

        gap = cls(L, TTF, TTFprime, TTFprimeprime, EField, phase, F, atten)
        gap.gapID = Param(val = int(pynacList[0]), unit = None)
        gap.energy = Param(val = float(pynacList[1]), unit = 'MeV')
        gap.beta = Param(val = float(pynacList[2]), unit = None)
        gap.S = Param(val = float(pynacList[6]), unit = None)
        gap.SP = Param(val = float(pynacList[7]), unit = None)
        gap.quadLength = Param(val = float(pynacList[8]), unit = 'cm')
        gap.quadStrength = Param(val = float(pynacList[9]), unit = 'kG/cm')
        gap.accumLen = Param(val = float(pynacList[12]), unit = 'cm')

        return gap