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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 store(self, database, validate=True, role=None):
 """Store the document in the given database. :param database: the `Database` object source for storing the document. :return: an updated instance of `Document` / self. """

        if validate:
            self.validate()
        self._id, self._rev = database.save(self.to_primitive(role=role))
        return self