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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 vcontoursf1D(self, x1, x2, nx, levels, labels=False, decimals=0, color=None, nudge=1e-6, newfig=True, figsize=None, layout=True, ax=None):
 """ Vertical contour for 1D model """

        naq = self.aq.naq
        xflow = np.linspace(x1 + nudge, x2 - nudge, nx)
        Qx = np.empty((naq, nx))
        for i in range(nx):
            Qx[:, i], Qydump = self.disvec(xflow[i], 0)
        zflow = np.empty(2 * naq)
        for i in range(self.aq.naq):
            zflow[2 * i] = self.aq.zaqtop[i]
            zflow[2 * i + 1] = self.aq.zaqbot[i]
        Qx = Qx[::-1] # set upside down
        Qxgrid = np.empty((2 * naq, nx))
        Qxgrid[0] = 0
        for i in range(naq - 1):
            Qxgrid[2 * i + 1] = Qxgrid[2 * i] - Qx[i]
            Qxgrid[2 * i + 2] = Qxgrid[2 * i + 1]
        Qxgrid[-1] = Qxgrid[-2] - Qx[-1]
        Qxgrid = Qxgrid[::-1] # index 0 at top
        if newfig:
            fig, ax = plt.subplots(1, 1, figsize=figsize)
        else:
            ax=ax
        cs = ax.contour(xflow, zflow, Qxgrid, levels, colors=color)
        if labels:
            fmt = '%1.' + str(decimals) + 'f'
            plt.clabel(cs, fmt=fmt)