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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 candidates(self):
 """Generates list of candidates from the DOM."""

        dom = self.dom
        if dom is None or len(dom) == 0:
            return None

        candidates, unlikely_candidates = find_candidates(dom)
        drop_nodes_with_parents(unlikely_candidates)

        return candidates