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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_title(self, title, level=1, id=None):
 """Writes a title header in the document body, with an optional depth level """

        if id:
            self.write('<h{lv} id="{id}">{title}</h{lv}>',
                       title=title, lv=level, id=id)
        else:
            self.write('<h{lv}>{title}</h{lv}>',
                       title=title, lv=level)