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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 ``Set4DAperture`` instance from the Pynac lattice element """

        energyDefnFlag = int(pynacRepr[1][0][0])
        energy = float(pynacRepr[1][0][1])
        phase = float(pynacRepr[1][0][2])
        x = float(pynacRepr[1][0][3])
        y = float(pynacRepr[1][0][4])
        radius = float(pynacRepr[1][0][5])

        return cls(energy, phase, x, y, radius, energyDefnFlag)