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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 remove_fact(self, fact_id):
 """Remove fact from storage by it's ID"""

        self.start_transaction()
        fact = self.__get_fact(fact_id)
        if fact:
            self.__remove_fact(fact_id)
            self.facts_changed()
        self.end_transaction()