Is there a way to add a new axis to a bokeh graph after it is already being displayed?

I'm trying to update a figure that is being run on a bokeh server. I found out that you can use figure.extra_y_ranges = {'name':Range1d(0,10)} and then calling figure.add_layout(LinearAxis(y_range_name='name'),'right') to add a new y-axis with the range of 0-10 to my figure. However this only works for me if I do it right after initiating the figure. What I'm trying to do however is that the new y-axis is being added on a button click.

Here is a simplified version of the code I'm running:

from bokeh.io import curdoc
from bokeh.plotting import figure
from bokeh.models import LinearAxis, Range1d
from bokeh.models.widgets import Button
from bokeh.layouts import column, row, grid

def update_fig(fig):
    fig.extra_y_ranges = {'a':Range1d(0,10)}
    fig.add_layout(LinearAxis(y_range_name='a', axis_label='a'), 'left')

def update_axis():
    update_fig(fig)

fig = figure()
fig.circle_dot([1,2,3,4],[1,2,3,4])
update_fig(fig) # This works

value_sel = Button(label='Add y-axis')
value_sel.on_click(update_axis) # This doesn't work

layout = row(
    column(value_sel),
    grid(fig)
    )

curdoc().add_root(layout)

I'm then running the function with bokeh serve --show example.py

I'd appreciate any help, thanks!