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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 box_it_up(self):
 """ Perform value lookup for all items in current dictionary, generating all sub Box objects, while also running `box_it_up` on any of those sub box objects. """

        for k in self:
            _conversion_checks(k, self.keys(), self._box_config,
                               check_only=True)
            if self[k] is not self and hasattr(self[k], 'box_it_up'):
                self[k].box_it_up()