Program:

class Queue:
    def __init__(self):
        self.items = []
 
    def is_empty(self):
        return self.items == []
 
    def enqueue(self, data):
        self.items.append(data)
 
    def dequeue(self):
        return self.items.pop(0)


    
q=Queue()  
  
q.enqueue(10)
q.enqueue(20)
q.enqueue(30)
q.enqueue(40)
print(q.items)
q.dequeue()
print(q.items)

Expected O/P:

[10, 20, 30, 40]
[20, 30, 40]