@abc.abstractmethod<EOL><INDENT>def remove_child(self, id_, child_id):<DEDENT>
pass<EOL>
Removes a childfrom an ``Id``.

        :param id: the ``Id`` of the node
        :type id: ``osid.id.Id``
        :param child_id: the ``Id`` of the child to remove
        :type child_id: ``osid.id.Id``
        :raise: ``NotFound`` -- ``id`` or ``child_id`` was not found or ``child_id`` is not a child of ``id``
        :raise: ``NullArgument`` -- ``id`` or ``child_id`` is ``null``
        :raise: ``OperationFailed`` -- unable to complete request
        :raise: ``PermissionDenied`` -- authorization failure

        *compliance: mandatory -- This method must be implemented.*