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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 _mark_entities(self, c, markers):
 """ Convert Snorkel candidates to marked up sequences :param c: :param markers: :return: """

        sent = c.get_parent().words
        positions = [
            [c[i].get_word_start(), c[i].get_word_end()]
            for i in range(self.cardinality)
        ]
        seq = mark_entities(sent, positions, markers=markers, style="insert")
        return [w for w in seq if w.strip()]