def close$\_$existing$\_$invoice$($self$,$ invoice$\_$number$)$:

try:

with open$($self$.$registry.file$\_$path, $\text{'}$r$\text{'})$ as file:

invoice$\_$found $=$ False

for line in file:

if line.strip$()==$ f$"$Invoice Number: $\{$invoice$\_$number$\}"$:

invoice$\_$found $=$ True

break

if invoice$\_$found:

customer$\_$info $=\{\}$

for $\_$ in range$(4)$: # Read customer info lines

key, value $=$ file.readline$().$split$("$: $",1)$

customer$\_$info$[$key$]=$ value.strip$()$

products $=\{\}$

while True:

line $=$ file.readline$().$strip$()$

if not line or line $==$ "Amount Paid:":

break

model$\_$number, price $=$ line.split$("$: $")[0],$ float$($line$.$split$("$: $")[1])$

products$[$model$\_$number$]=\{\text{'}$name$\text{'}$: self.product$\_$catalog.products$[$model$\_$number$][\text{'}$name$\text{'}],$ 'price': price$\}$

amount$\_$paid $=$ float$($file$.$readline$().$split$("$: $")[1])$

total $=$ sum$($product$[\text{'}$price$\text{'}]$ for product in products.values$())$

if amount$\_$paid $>=$ total:

print$("$Invoice already fully paid."$)$

else:

print$("$This invoice still has an outstanding balance."$)$

else:

print$("$Invoice not found."$)$

except FileNotFoundError:

print$("$Registry file not found."$)$

def return$\_$product$($self$,$ invoice$\_$number$)$:

try:

invoice$\_$info $=$ self.get$\_$invoice$\_$info$($invoice$\_$number$)$

if invoice$\_$info:

total$\_$amount $=$ invoice$\_$info$[\text{'}$total$\text{'}]$

amount$\_$paid $=$ invoice$\_$info$[\text{'}$amount$\_$paid'$]$

returned$\_$amount $=$ float$($input$("$Enter the amount of returned product: $$"))$

if returned$\_$amount $<=$ total$\_$amount $-$ amount$\_$paid:

customer$\_$info $=$ invoice$\_$info$[\text{'}$customer$\_$info'$]$

products $=$ invoice$\_$info$[\text{'}$products$\text{'}]$

products$[\text{'}$Returned Product'$]=\{\text{'}$name$\text{'}$: 'Returned Product', 'price': $-$returned$\_$amount$\}$

returned$\_$invoice $=$ Invoice$($invoice$\_$number, customer$\_$info, products$)$

self.registry.save$\_$invoice$($returned$\_$invoice$)$

print$("$

Return processed successfully!

$")$

print$($returned$\_$invoice.generate$\_$invoice$())$

else:

print$("$Returned amount exceeds the remaining balance."$)$

else:

print$("$Invoice not found."$)$

except Exception as e:

print$($f$"$ErrOutput:

Select an option:

$1.$ Generate a new invoice

$2.$ Close an existing invoice

$3.$ Return a product

$4.$ Get a quote

$5.$ Quit

Enter your choice: $2$

Enter the invoice number to close: $1$

Error: not enough values to unpack $($expected $2,$ got $1)$or: $\{$str$($e$)\}")$

Please fix this error, same issue with both return and close invoice