starting mypy with maze

src/amaz_lib/Maze.py

@@ -1,16 +1,16 @@
 from dataclasses import dataclass
-
-import numpy
+from numpy.typing import NDArray
+from typing import Optional, Any
 
 
 @dataclass
 class Maze:
-    maze: numpy.ndarray
+    maze: Optional[NDArray[Any]] = None
 
-    def get_maze(self) -> numpy.ndarray | None:
+    def get_maze(self) -> Optional[NDArray[Any]]:
         return self.maze
 
-    def set_maze(self, new_maze: numpy.ndarray) -> None:
+    def set_maze(self, new_maze: NDArray[Any]) -> None:
         self.maze = new_maze
 
     def __str__(self) -> str:
@@ -24,6 +24,9 @@ class Maze:
         return res
 
     def ascii_print(self) -> None:
+        if self.maze is None:
+            print("None")
+            return
         for cell in self.maze[0]:
             print("_", end="")
             if cell.get_north():