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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def __i(self, other, func):
 """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)."""


        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