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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 get_xy_name(self, yidx, xidx=0):
 """ Return variable names for the given indices :param yidx: :param xidx: :return: """

        assert isinstance(xidx, int)
        if isinstance(yidx, int):
            yidx = [yidx]

        uname = ['Time [s]'] + self.uname
        fname = ['$Time\\ [s]$'] + self.fname

        xname = [list(), list()]
        yname = [list(), list()]

        xname[0] = uname[xidx]
        xname[1] = fname[xidx]

        yname[0] = [uname[i] for i in yidx]
        yname[1] = [fname[i] for i in yidx]

        return xname, yname