class RollercoasterQueue:

def $\_\_$init$\_\_($self$,$ ride$\_$seats, ride$\_$length$)$:

self.$\_\_$ride$\_$seats $=$ ride$\_$seats

self.$\_\_$ride$\_$length $=$ ride$\_$length

self.$\_\_$queue$\_$length $=0$

def board$\_$ride$($self$)$:

if self.$\_\_$queue$\_$length self.$\_\_$ride$\_$seats:

self.$\_\_$queue$\_$length $=0$

else:

self.$\_\_$queue$\_$length $-=$ self.$\_\_$ride$\_$seats

def enqueue$($self$)$:

self.$\_\_$queue$\_$length $+=1$

def length$($self$)$:

return self.$\_\_$queue$\_$length

# Sample run code

def main$()$:

ride$\_$seats $=$ int$($input$("$How many people fit in one ride? $"))$

ride$\_$length $=$ int$($input$("$How long is the ride, in minutes? $"))$

rc$\_$queue $=$ RollercoasterQueue$($ride$\_$seats, ride$\_$length$)$

# Enqueue $20$ people

for $\_$ in range$(20)$:

rc$\_$queue.enqueue$()$

print$($f$"$Queue length after enqueue: $\{$rc$\_$queue.length$()\}")$

# Board ride until the queue is empty

while rc$\_$queue.length$()>0$:

rc$\_$queue.board$\_$ride$()$

print$($f$"$Queue length after boarding: $\{$rc$\_$queue.length$()\}")$

if $\_\_$name$\_\_=="\_\_$main$\_\_"$:

main$()$

It looks like you did not store your instance in $\text{'}$rc$\_$queue'.