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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 _write_fact(self, fact_tuple):
 """ Create new fact element and populate attributes. Once the child is prepared append it to ``fact_list``. """

        fact = self.document.createElement("fact")
        fact.setAttribute('start', fact_tuple.start)
        fact.setAttribute('end', fact_tuple.end)
        fact.setAttribute('activity', fact_tuple.activity)
        fact.setAttribute('duration', fact_tuple.duration)
        fact.setAttribute('category', fact_tuple.category)
        fact.setAttribute('description', fact_tuple.description)
        self.fact_list.appendChild(fact)