def run(self, root):
        """ Add linebreaks to ElementTree root object. """

        self._prettifyETree(root)
        # Do <br />'s seperately as they are often in the middle of
        # inline content and missed by _prettifyETree.
        brs = root.getiterator('br')
        for br in brs:
            if not br.tail or not br.tail.strip():
                br.tail = '\n'
            else:
                br.tail = br.tail % '\n%s'
dataset/ETHPy150Open natestedman/Observatory/observatory/lib/markdown/treeprocessors.py/PrettifyTreeprocessor.run/swapped operands of `%`