Write a queue class MyQueue with a default constructor and three functions: push(val) - adds a value to the queue, front() - returns the first element in the queue, pop() - removes the first element in the queue.

class MyQueue:
    
    def __init__(self):
        self.data = []
        
    def push(self, val):
        self.data.append(val)
        
    def front(self):
        if len(self.data) == 0:
            return -1
        return self.data[0]
    
    def pop(self):
        if len(self.data) == 0:
            return -1
        return self.data.pop(0)