diff --git a/erddapy/core/url.py b/erddapy/core/url.py
index f8928b3..b2472d7 100644
--- a/erddapy/core/url.py
+++ b/erddapy/core/url.py
@@ -3,7 +3,6 @@
 import copy
 import functools
 import io
-import os
 from collections import OrderedDict
 from datetime import datetime
 from typing import BinaryIO