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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 _set_child(self, name, child):
 """ Set child. :param name: Child name. :param child: Parentable object. """

        if not isinstance(child, Parentable):
            raise ValueError('Parentable child object expected, not {child}'.format(child=child))
        child._set_parent(self)
        self._store_child(name, child)