How can I draw the y-axis on both sides of a sns.relplot?

Question

relplot/lineplot

I like to have the y-axis also on the right hand side, to be able to see which values are reached at the end of the time series. I do not want a new y-axis, just the same one on both sides of a relplot. Is there any easy solution?

g=sns.relplot(x='year',
                  y=var,
                  data=df,
                  hue='exp',
                  hue_order=['rcp26','rcp45','rcp85'],
                  palette=colrcp,
                  kind='line',
                  row='region',
                  row_order=['Scandinavia','Alps', 'Iberian P.', 'Eastern E.'], 
                  height=2, aspect=6,
                  facet_kws={'sharey': False, 'sharex': True})