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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 of(cls, *passages: BioCPassage):
 """ Returns a collection passages """

        if len(passages) <= 0:
            raise ValueError("There has to be at least one passage.")
        c = BioCDocument()
        for passage in passages:
            if passage is None:
                raise ValueError('Passage is None')
            c.add_passage(passage)
        return c