Fix type hints for previous Python versions

lisainstrument/cache.py

@@ -12,6 +12,7 @@ import logging
 import multiprocessing as mp
 import os
 
+from typing import Dict, List
 from h5py import File
 
 from lisainstrument.containers import ForEachObject
@@ -41,9 +42,9 @@ class Cache:
     def __init__(self, filename: str, nprocess: int = 1, mode: str = "x") -> None:
         self.filename = filename
         self.nprocess = nprocess
-        self.cache: dict[str, ForEachObject] = {}
+        self.cache: Dict[str, ForEachObject] = {}
 
-        self.processes: list[mp.Process] = []
+        self.processes: List[mp.Process] = []
         self.temp_filenames = [f"{self.filename}.{i}" for i in range(nprocess)]
         self.queue: mp.Queue = mp.Queue()