diff --git a/src/cloudforet/cost_analysis/connector/azure_cost_mgmt_connector.py b/src/cloudforet/cost_analysis/connector/azure_cost_mgmt_connector.py
index 471eabd..41bf3f5 100644
--- a/src/cloudforet/cost_analysis/connector/azure_cost_mgmt_connector.py
+++ b/src/cloudforet/cost_analysis/connector/azure_cost_mgmt_connector.py
@@ -5,7 +5,7 @@
 from datetime import datetime
 from functools import wraps
 from io import BytesIO
-from typing import get_type_hints, Union, Any
+from typing import get_type_hints, Union, Any, Generator
 
 import numpy as np
 import pandas as pd