helper_classes.py

from typing import Callable, Tuple
from copy import deepcopy
from dataclasses import dataclass, field
from typing import Dict, List, Tuple
from copy import deepcopy
import heapq

@dataclass
class Node:
    matrix: Matrix
    parent: 'Node' = None
    cost: float = float('inf')
    depth: int = float('inf')

    def __hash__(self) -> int:
        return hash(str(self.matrix))


@dataclass(order=True)
class PriorityItem:
    priority: int
    item: Node = field(compare=False)


class PriorityQueue:
    def __init__(self) -> None:
        self._list = []

    def add(self, node: Node) -> None:
        heapq.heappush(self._list, PriorityItem(node.cost + node.depth, node))

    def pop(self) -> Node:
        return heapq.heappop(self._list).item

    def isempty(self) -> bool:
        return len(self._list) == 0

    def __contains__(self, node: Node) -> bool:
        return node in self._list