python3 support (#42)

* refactor imports

* python3 compatibility

Author: christophgysin

dynamodump.py

@@ -1,4 +1,4 @@
-#!/usr/bin/env python2
+#!/usr/bin/env python
 """
     Simple backup and restore script for Amazon DynamoDB using boto to work similarly to mysqldump.
 
@@ -15,15 +15,24 @@
 import os
 import shutil
 import threading
-import Queue
 import datetime
 import errno
 import sys
 import time
 import re
 import zipfile
 import tarfile
-import urllib2
+
+try:
+    from queue import Queue
+except ImportError:
+    from Queue import Queue
+
+try:
+    from urllib.request import urlopen
+    from urllib.error import URLError, HTTPError
+except ImportError:
+    from urllib2 import urlopen, URLError, HTTPError
 
 import boto.dynamodb2.layer1
 from boto.dynamodb2.exceptions import ProvisionedThroughputExceededException
@@ -63,13 +72,13 @@ def _get_aws_client(profile, region, service):
     # Fallback to querying metadata for region
     if not aws_region:
         try:
-            azone = urllib2.urlopen(METADATA_URL + "placement/availability-zone",
-                                    data=None, timeout=5).read().decode()
+            azone = urlopen(METADATA_URL + "placement/availability-zone",
+                            data=None, timeout=5).read().decode()
             aws_region = azone[:-1]
-        except urllib2.URLError:
+        except URLError:
             logging.exception("Timed out connecting to metadata service.\n\n")
             sys.exit(1)
-        except urllib2.HTTPError as e:
+        except HTTPError as e:
             logging.exception("Error determining region used for AWS client.  Typo in code?\n\n" +
                               str(e))
             sys.exit(1)
@@ -913,7 +922,7 @@ def main():
         except AttributeError:
             # Didn't specify srcTable if we get here
 
-            q = Queue.Queue()
+            q = Queue()
             threads = []
 
             for i in range(MAX_NUMBER_BACKUP_WORKERS):