Could you please modify this script to be able to decrypt entire files of text?

code $=$ input$("$Enter the coded text $")$

distance $=$ int$($input$("$Enter the distance value $")$

plainText $=""$

for ch in code: ordvalue $=$ ord$($ch$)$ cipherValue $=$ ordvalue $-$ distance

if cipherValue $<$ ord$(\text{'}$a$\text{'})$: cipherValue $=$ ord$(\text{'}$z$\text{'})-($distance$-($ord$(\text{'}$a$\text{'})-$ ordvalue$-1))$ plainText $+=$ chr$($cipherValue$)$ print$($plainText$)$