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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 union(self, other):
 """ Returns a FrozenList with other concatenated to the end of self. Parameters other : array-like The array-like whose elements we are concatenating. Returns ------- diff : FrozenList The collection difference between self and other. """

        if isinstance(other, tuple):
            other = list(other)
        return type(self)(super().__add__(other))