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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 _join_parameters(base, nxt):
 """ join parameters from the lhs to the rhs, if compatible. """

        if nxt is None:
            return base
        if isinstance(base, set) and isinstance(nxt, set):
            return base | nxt
        else:
            return nxt