Fix problems from pyflakes output

mediagoblin/storage/__init__.py

@@ -14,9 +14,7 @@
 # You should have received a copy of the GNU Affero General Public License
 # along with this program.  If not, see <http://www.gnu.org/licenses/>.
 
-import os
 import shutil
-import urlparse
 import uuid
 
 from werkzeug.utils import secure_filename

mediagoblin/storage/cloudfiles.py

@@ -73,8 +73,7 @@ class CloudFilesStorage(StorageInterface):
 
     def file_exists(self, filepath):
         try:
-            object = self.container.get_object(
-                self._resolve_filepath(filepath))
+            self.container.get_object( self._resolve_filepath(filepath))
             return True
         except cloudfiles.errors.NoSuchObject:
             return False

mediagoblin/storage/mountstorage.py

@@ -17,6 +17,10 @@
 from mediagoblin.storage import StorageInterface, clean_listy_filepath
 
 
+class MountError(Exception):
+    pass
+
+
 class MountStorage(StorageInterface):
     """
     Experimental "Mount" virtual Storage Interface
@@ -105,7 +109,7 @@ class MountStorage(StorageInterface):
     def resolve_to_backend(self, filepath):
         backend, filepath = self._resolve_to_backend(filepath)
         if backend is None:
-            raise Error("Path not mounted")
+            raise MountError("Path not mounted")
         return backend, filepath
 
     def __repr__(self, table=None, indent=[]):