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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 to_dict(self, **kwargs):
 """ Serialize the search into the dictionary that will be sent over as the request'ubq body. All additional keyword arguments will be included into the dictionary. """

        d = {}
        if self.query:
            d["query"] = self.query.to_dict()

        if self._script:
            d['script'] = self._script

        d.update(self._extra)

        d.update(kwargs)
        return d