Can someone help me fix my code. The instructions are:

Complete the function NFA$($input$\_$string, nfa$)$ that runs an NFA.

In particuar, modify the code on the following lines:

$-$ line $20$: initialize current$\_$states $($note the plural!$)$

$-$ line $27$: define x

$-$ line $40$: define the NFA given in Figure $8\mathrm{.}2$; use, as an example, the definition of dfa$1$ given in line $40$

$-$ n is $5,$ so the $5$th symbol from the end should be $1,$ it should reject $"01010101111111111001010000111110000000"$

class FA:

def $\_\_$init$\_\_($self$,$ alphabet, states, transition, accepting$\_$states$)$:

self.alphabet $=$ alphabet

self.states $=$ states

self.transition $=$ transition

self.accepting$\_$states $=$ accepting$\_$states

def DFA$($input$\_$string, dfa$)$:

# set current$\_$state to initial state

current$\_$state $=$ dfa.states$[0]$

# run through the input string

for symbol in input$\_$string:

i $=$ dfa.states.index$($current$\_$state$)$

j $=$ dfa.alphabet.index$($symbol$)$

current$\_$state $=$ dfa.transition$[$i$][$j$]$

return current$\_$state

def NFA$($input$\_$string, nfa$)$:

# set current$\_$state to initial state

current$\_$states $=\{$nfa$.$states$[0]\}$

# run through the input string

for symbol in input$\_$string:

x $=$ set$()$

for state in current$\_$states:

i $=$ nfa.states.index$($state$)$

j $=$ nfa.alphabet.index$($symbol$)$

x $|=$ set$($nfa$.$transition$[$i$][$j$])$

current$\_$states $=$ x

return current$\_$states

def main$()$:

# Read in the input$\_$string

input$\_$string $=$ input$()$

# Define a DFA

dfa$1=$ FA$([\text{'}0\text{'},\text{'}1\text{'}],[\text{'}$q$\text{'},\text{'}$r$\text{'}],[[\text{'}$r$\text{'},\text{'}$q$\text{'}],[\text{'}$q$\text{'},\text{'}$r$\text{'}]],\{\text{'}$q$\text{'}\})$

# Define the NFA given in Figure $8\mathrm{.}2$ for n$=5$

nfa$1=$ FA$([\text{'}0\text{'},\text{'}1\text{'}],[\text{'}$q$\text{'},\text{'}$r$\text{'},\text{'}$s$\text{'},\text{'}$t$\text{'},\text{'}$u$\text{'}],[[[\text{'}$q$\text{'}],[\text{'}$q$\text{'},\text{'}$r$\text{'}]],[[\text{'}$s$\text{'}],[\text{'}$s$\text{'}]],[[\text{'}$t$\text{'}],[\text{'}$t$\text{'}]],[[\text{'}$u$\text{'}],[\text{'}$u$\text{'}]]],\{\text{'}$u$\text{'}\})$

# Run the DFA on the input stri

# final$\_$state $=$ DFA$($input$\_$string, dfa$1)$

# if final$\_$state in dfa$1.$accepting$\_$states:

# print$("$Accept$")$

# else:

# print$("$Reject$")$

# Run the NFA on the input string

final$\_$states $=$ NFA$($input$\_$string, nfa$1)$

if set$($final$\_$states$)$ & set$($nfa$1.$accepting$\_$states$)$:

print$("$Accept$")$

else:

print$("$Reject$")$

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

main$()$