Update to python 3 syntax

Author: Razvan Nesiu

django_google_storage/file.py

@@ -1,11 +1,6 @@
 # coding=utf-8
 from django.core.files.base import File
-
-try:
-    from cStringIO import StringIO
-except ImportError:
-    from StringIO import StringIO
-
+from io import StringIO
 
 class GSBotoStorageFile(File):
     def __init__(self, name, mode, storage):

django_google_storage/format.py

@@ -1,5 +1,5 @@
 # coding=utf-8
-import urllib
+import urllib.request, urllib.parse, urllib.error
 
 import boto.utils
 from boto.exception import BotoClientError
@@ -44,11 +44,11 @@ def build_auth_path(self, bucket, key=''):
         path = ''
         if bucket != '':
             path = '/' + bucket
-        return path + '/%s' % urllib.quote(key)
+        return path + '/%s' % urllib.parse.quote(key)
 
     def build_path_base(self, bucket, key=''):
         key = boto.utils.get_utf8_value(key)
-        return '/%s' % urllib.quote(key)
+        return '/%s' % urllib.parse.quote(key)
 
 
 class SubdomainCallingFormat(_CallingFormat):

django_google_storage/storage.py

@@ -108,7 +108,7 @@ def _get_or_create_bucket(self, name):
         """Retrieves a bucket if it exists, otherwise creates it."""
         try:
             return self.connection.get_bucket(name, validate=AUTO_CREATE_BUCKET)
-        except Exception, e:
+        except Exception as e:
             if AUTO_CREATE_BUCKET:
                 bucket = self.connection.create_bucket(name)
                 bucket.set_acl(self.bucket_acl)

django_google_storage/utils.py

@@ -13,9 +13,9 @@ def safe_join(base, *paths):
 
     Paths outside the base path indicate a possible security sensitive operation.
     """
-    from urlparse import urljoin
+    from urllib.parse import urljoin
     base_path = force_unicode(base)
-    paths = map(lambda p: force_unicode(p), paths)
+    paths = [force_unicode(p) for p in paths]
     final_path = urljoin(base_path + ("/" if not base_path.endswith("/") else ""), *paths)
     # Ensure final_path starts with base_path and that the next character after
     # the final path is '/' (or nothing, in which case final_path must be