ax3.spines['left'].set_position('zero') does not work

This code results in python

    from plotly import tools
    import plotly.plotly as py
    import plotly.graph_objs as go


    fig = figure()
    ax3 = subplot2grid((2,2),(0,1),rowspan=2)
    ax1 = subplot2grid((2,2),(0,0))
    ax2 = subplot2grid((2,2),(1,0))



    ax1.plot([-1,2],[-5,2])
    ax2.plot([-1,2],[-2,3])
    ax3.plot([-4,2],[-7,3])


    ax3.spines['left'].set_position('zero')
    ax3.spines['right'].set_color('none')
    ax3.spines['bottom'].set_position('zero')
    ax3.spines['top'].set_color('none')
    ax3.spines['left'].set_smart_bounds(True)
    ax3.spines['bottom'].set_smart_bounds(True)
    suptitle(Cell1)
    plot_url = py.plot_mpl(fig)