code: def targets_format(self, value):
          
  
          if value is not None:
              assert type(value) is unicode, "'{0}' attribute: '{1}' type is not 'unicode'!".format(
                  "targets_format", value)
              assert os.path.exists(value), "'{0}' attribute: '{1}' file doesn't exists!".format("targets_format", value)
          self.__targets_format = value
docs: Setter for **self.__targets_format** attribute.
  
          :param value: Attribute value.
          :type value: unicode