code: def __i(self, other, func):
          
  
          if isinstance(other, type(self)):
              other = tuple(other)
  
          elif isinstance(other, self.__contenttype__):
              other = (other, )
  
          for melt in list(other):
              if not isinstance(melt, self.__contenttype__):
                  raise TypeError('Wrong element {0}'.format(melt))
  
              else:
                  func(melt)
  
          return self
docs: Process input other with input func.
  
          :param ModelElement(s) other: other ModelElement(s) to process.
          :param func: function to apply on a ModelElement.
          :return: self.
          :raise: TypeError if other is not a ModelElement(s).