Use typing instead of init function

Author: AndyTitu

src/onepassword/client.py

@@ -6,20 +6,23 @@
 
 
 class Client:
-    def __init__(self, client_id):
-        self.secrets = Secrets(client_id)
-        self.items = Items(client_id)
+    secrets: Secrets
+    items: Items
 
     @classmethod
-    async def authenticate(cls, auth, integration_name, integration_version):
+    async def authenticate(self, auth, integration_name, integration_version):
         config = new_default_config(
             auth=auth,
             integration_name=integration_name,
             integration_version=integration_version,
         )
         client_id = int(await _init_client(config))
-        self = cls(client_id)
-        self._config = config
-        self._finalizer = weakref.finalize(self, _release_client, client_id)
 
-        return self
+        authenticated_client = self()
+
+        authenticated_client.secrets = Secrets(client_id)
+        authenticated_client.items = Items(client_id)
+        authenticated_client._config = config
+        authenticated_client._finalizer = weakref.finalize(self, _release_client, client_id)
+
+        return authenticated_client