docs: def _get_existing_disposable_app(file, clientInfo, conf):
      """
      Attempt to load an existing 
      """
      if not os.path.isfile(file):
          return None
      else:
          data = None
          with open(file, 'r') as f:
              data = json.load(f)
          if not 'client' in data or not 'creds' in data:
              return None
          return _BlotreDisposableApp(file,
              data['client'],
              creds = data['creds'],
              config = conf)