chore: Use typing.NamedTuple for Operator in client.py (#669)

Signed-off-by: Adityarya11 <arya050411@gmail.com>

Author: Adityarya11

CHANGELOG.md

@@ -21,8 +21,12 @@ This changelog is based on [Keep a Changelog](https://keepachangelog.com/en/1.1.
 - chore: Update env.example NETWORK to encourage testnet or local usage (#659)
 - chore: fix type hint for TokenCancelAirdropTransaction pending_airdrops parameter
 - chore: Moved documentation file `common_issues.md` from `examples/sdk_developers/` to `docs/sdk_developers/` for unified documentation management (#516).
+
 - chore: Refactored the script of examples/custom_fee.py into modular functions 
 
+- fix: Replaced `collections.namedtuple` with `typing.NamedTuple` in `client.py` for improved type checking.
+
+
 ### Fixed
 
 - Added explicit read permissions to examples.yml (#623)

src/hiero_sdk_python/client/client.py

@@ -2,8 +2,7 @@
 Client module for interacting with the Hedera network.
 """
 
-from collections import namedtuple
-from typing import List, Union
+from typing import NamedTuple, List, Union
 
 import grpc
 
@@ -18,7 +17,10 @@
 
 from .network import Network
 
-Operator = namedtuple('Operator', ['account_id', 'private_key'])
+class Operator(NamedTuple):
+    """A named tuple for the operator's account ID and private key."""
+    account_id: AccountId
+    private_key: PrivateKey
 
 class Client:
     """
@@ -112,4 +114,4 @@ def __exit__(self, exc_type, exc_value, traceback) -> None:
         """
         Automatically close channels when exiting 'with' block.
         """
-        self.close()
+        self.close()