Queue

class Queue:
    def __init__(self):
        self.q = []
        
    def enQueue(self, item):
        self.q.append(item)
    
    def isEmpty(self):
        return len(self.q) == 0
    
    def deQueue(self):
        if self.isEmpty() == False:
            return self.q.pop(0)
        else:
            return None
    
    def peek(self):
        if self.isEmpty() == False:
            return self.q[0]
        else:
            return None