Support Python 3 using six

moto/sqs/models.py

@@ -30,7 +30,7 @@ class Message(object):
     @property
     def md5(self):
         body_md5 = hashlib.md5()
-        body_md5.update(self.body)
+        body_md5.update(self.body.encode('utf-8'))
         return body_md5.hexdigest()
 
     def mark_sent(self, delay_seconds=None):

moto/sqs/utils.py

@@ -7,7 +7,7 @@ import string
 def generate_receipt_handle():
     # http://docs.aws.amazon.com/AWSSimpleQueueService/latest/SQSDeveloperGuide/ImportantIdentifiers.html#ImportantIdentifiers-receipt-handles
     length = 185
-    return ''.join(random.choice(string.lowercase) for x in range(length))
+    return ''.join(random.choice(string.ascii_lowercase) for x in range(length))
 
 
 def unix_time(dt=None):