Priority function for priority queue not returning string in Python

I'm trying to implement a priority queue using an array list of my PQElement’s. I am stuck on dequeueing from the priority queue the PQ-element with the greatest priority so that I can print elements of the priority queue into a string, in order of decreasing priority.

Any idea on how to go about this?

class PQElement:
    def __init__(self, v, p):
        self.val = v
        self.priority = p
            
    def __str__(self):
        return "("+str(self.val)+","+str(self.priority)+")"
        
class PQueue:
    def __init__(self):
        self.inList = []
        
    def __len__(self):
        return len(self.inList)

    def ___str__(self,):
        return str(self.inList)
    
    def enq(self, e): # insert (tail)
        self.inList.append(e)   
        
    def deq(self): # remove
        if len(self)==0:
            raise IndexError("deq from empty queue")
        max_priority = self.inList[0].priority
        max_idx = 0
        for idx, elmt in enumerate(self.inList):
            if elmt.priority > max_priority:
                max_priority = elmt.priority
                max_idx = idx
        return self.inList.pop(max_idx)