existing code

class CircularQueue:

def __init__(self, capacity = 8):

self.capacity = capacity

self.front = 0

self.count = 0

self.back = capacity - 1

self.items = [None] * capacity

def __str__(self):

a_list = []

for i in range(self.count):

j = (self.back - i) % len(self.items)

item = self.items[j]

a_list.append(item)

return '-> |{}| ->'.format(', '.join([repr(item) for item in a_list]))

def enqueue(self, item):

if not self.is_full():

self.back = (self.back + 1) % self.capacity

self.items[self.back] = item

self.count += 1

else:

raise IndexError('ERROR: The queue is full.')

def dequeue(self):

if not self.is_empty():

item = self.items[self.front]

self.front = (self.front + 1) % self.capacity

self.count -= 1

return item

else:

raise IndexError('ERROR: The queue is empty.')

def is_empty(self):

return self.count == 0

def is_full(self):

return self.count == self.capacity

def create_new_circular_queue(self, number):