old_contents: import os
  
  BUCKET_NAME = 'landsat-pds'
  BUCKET_URL = 'https://s3-us-west-2.amazonaws.com/landsat-pds'
  ACCESS_ID = os.environ['LANDSAT_PDS_ACCESS_ID']
  ACCESS_KEY = os.environ['LANDSAT_PDS_ACCESS_KEY']
  
  
new_contents: import os
  
  BUCKET_NAME = 'landsat-pds'
  BUCKET_URL = 'https://s3-us-west-2.amazonaws.com/landsat-pds'
  
  ACCESS_ID = os.environ.get('LANDSAT_PDS_ACCESS_ID',None)
  ACCESS_KEY = os.environ.get('LANDSAT_PDS_ACCESS_KEY',None)
  
  if ACCESS_ID is None or ACCESS_KEY is None:
      print
      print 'WARNING: Missing one or both of LANDSAT_PDS_ACCESS_ID and '
      print '         LANDSAT_PDS_ACCESS_KEY environment variables.'
      print
  
subject: improve error handling without access keys