class Queue:
    def __init__(self):
        self.queue = []

    def is_empty(self):
        return len(self.queue) == 0

    def enqueue(self, item):
            self.queue.append(item)

    def dequeue(self):
        if not self.empty():
            return self.queue[0]

    def peek(self):
        if not self.empty():
            return self.queue[0]
        
# enenqueue = dodowanie do kolejki
# dequeue = odejmowanie do kolejki