def backwards$\_$alphabet$($curr$\_$letter$)$:

if curr$\_$letter $==\text{'}$a$\text{'}$:

print$($curr$\_$letter$)$

else:

print$($curr$\_$letter$)$

prev$\_$letter $=$ chr$($ord$($curr$\_$letter$)-1)$

backwards$\_$alphabet$($prev$\_$letter$)$

starting$\_$letter $=$ input$()$

$\text{'}\text{'}\text{'}$ Your solution goes here $\text{'}\text{'}$