code: def paths(self, value):
          
  
          if value is not None:
              assert type(value) in (tuple, list), "'{0}' attribute: '{1}' type is not 'tuple' or 'list'!".format(
                  "paths", value)
              for element in value:
                  assert type(element) is unicode, "'{0}' attribute: '{1}' type is not 'unicode'!".format(
                      "paths", element)
                  assert os.path.exists(element), "'{0}' attribute: '{1}' directory doesn't exists!".format("paths",
                                                                                                            element)
          self.__paths = value
docs: Setter for **self.__paths** attribute.
  
          :param value: Attribute value.
          :type value: tuple or list