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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 normalize_lms_axis(ax, xlim=None, ylim=None, xfactor=1e-6, yfactor=1, xlabel=None, ylabel="Map (cM)"):
 """ Normalize the axis limits and labels to beautify axis. """

    if xlim:
        ax.set_xlim(0, xlim)
    if ylim:
        ax.set_ylim(0, ylim)
    if xlabel:
        xticklabels = [int(round(x * xfactor)) for x in ax.get_xticks()]
        ax.set_xticklabels(xticklabels, family='Helvetica')
        ax.set_xlabel(xlabel)
    else:
        ax.set_xticks([])
    if ylabel:
        yticklabels = [int(round(x * yfactor)) for x in ax.get_yticks()]
        ax.set_yticklabels(yticklabels, family='Helvetica')
        ax.set_ylabel(ylabel)
    else:
        ax.set_yticks([])