diff --git a/onesky/client.py b/onesky/client.py
index ef64ba7..c28bb80 100644
--- a/onesky/client.py
+++ b/onesky/client.py
@@ -22,9 +22,8 @@ def __init__(self, api_key, api_secret,
     def create_auth_variables(self):
         timestamp = str(int(time.time()))
 
-        dev_hash = hashlib.md5()
-        dev_hash.update(timestamp)
-        dev_hash.update(self.api_secret)
+        hash_key = str(timestamp) + self.api_secret
+        dev_hash = hashlib.md5(bytes(hash_key, 'utf-8'))
 
         return {
             'api_key': self.api_key,