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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 find_id(self, element_id):
 """Find element by its id. Parameters element_id : str ID of the element to find Returns ------- FigureElement one of the children element with the given ID."""

        find = etree.XPath("//*[@id=$id]")
        return FigureElement(find(self.root, id=element_id)[0])