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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 merge(cls, first, second):
 """ Return an AttributeList that is the result of merging first with second. """

        merged = AttributeList([], None)

        assert (isinstance(first, AttributeList))
        assert (isinstance(second, AttributeList))
        merged._contents = first._contents[:]
        merged._contents += second._contents[:]

        return merged