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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 update_one(self, update):
 """Update one document matching the selector. :Parameters: - `update` (dict):
 the update operations to apply """

        self.__bulk.add_update(self.__selector,
                               update, multi=False, upsert=True,
                               collation=self.__collation)