allow levels==0 to work (#3)

output was not defined before the levels==0 section (I guess nobody tested it when it was added...)

Author: dmd

dropbox_folder_size.py

@@ -10,6 +10,8 @@
 # If you just want to know overall usage of account (i.e. levels = 0), we will run a separate query for it
 levels = 2
 
+output = open('dropbox_folder_sizes.txt', 'w')
+
 if (levels == 0):
     quota_info = client.account_info()['quota_info']
     usage = quota_info['shared'] / (1024.0 ** denomination)
@@ -49,8 +51,6 @@
         else:
             del foldersizes[path]
 
-output = open('dropbox_folder_sizes.txt', 'w')
-
 output.write('Below is a list of your largest Dropbox folders, ordered from largest to smallest. You chose a drill level of 2. Sizes are expressed as "%d", where 0 is in bytes, 1 is in KB, 2 is in MB, and 3 is in GB. \n' % denomination)
 
 for folder in reversed(sorted(foldersizes.keys(), key=lambda x: foldersizes[x])):