diff --git a/todoist_api_python/api.py b/todoist_api_python/api.py
index fa727ab..b25c9f8 100644
--- a/todoist_api_python/api.py
+++ b/todoist_api_python/api.py
@@ -2,6 +2,8 @@
 
 from typing import Any, Dict, List
 
+from weakref import finalize
+
 import requests
 
 from todoist_api_python.endpoints import (
@@ -36,6 +38,13 @@ class TodoistAPI:
     def __init__(self, token: str, session: requests.Session | None = None) -> None:
         self._token: str = token
         self._session = session or requests.Session()
+        self._finalizer = finalize(self, self._session.close)
+        
+    def __enter__(self):
+        return self
+        
+    def __exit__(self, exc_type, exc_value, traceback):
+        self._finalizer()
 
     def get_task(self, task_id: str) -> Task:
         endpoint = get_rest_url(f"{TASKS_ENDPOINT}/{task_id}")