diff --git a/pytorch_transformers/tests/tokenization_tests_commons.py b/pytorch_transformers/tests/tokenization_tests_commons.py
index 4e5fe8370..44adbc6b5 100644
--- a/pytorch_transformers/tests/tokenization_tests_commons.py
+++ b/pytorch_transformers/tests/tokenization_tests_commons.py
@@ -14,6 +14,7 @@
 # limitations under the License.
 from __future__ import absolute_import, division, print_function, unicode_literals
 
+import os
 import sys
 from io import open
 import tempfile
@@ -49,15 +50,18 @@ def create_and_check_save_and_load_tokenizer(tester, tokenizer_class, *inputs, *
 
 def create_and_check_pickle_tokenizer(tester, tokenizer_class, *inputs, **kwargs):
     tokenizer = tokenizer_class.from_pretrained(*inputs, **kwargs)
+    tester.assertIsNotNone(tokenizer)
 
     text = u"Munich and Berlin are nice cities"
-    filename = u"/tmp/tokenizer.bin"
-
     subwords = tokenizer.tokenize(text)
 
-    pickle.dump(tokenizer, open(filename, "wb"))
+    with TemporaryDirectory() as tmpdirname:
+
+        filename = os.path.join(tmpdirname, u"tokenizer.bin")
+        pickle.dump(tokenizer, open(filename, "wb"))
+
+        tokenizer_new = pickle.load(open(filename, "rb"))
 
-    tokenizer_new = pickle.load(open(filename, "rb"))
     subwords_loaded = tokenizer_new.tokenize(text)
 
     tester.assertListEqual(subwords, subwords_loaded)