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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 addpattern(base_func):
 """Decorator to add a new case to a pattern-matching function, where the new case is checked last."""

    def pattern_adder(func):
        @_coconut.functools.wraps(func)
        @_coconut_tco
        def add_pattern_func(*args, **kwargs):
            try:
                return base_func(*args, **kwargs)
            except _coconut_MatchError:
                raise _coconut_tail_call(func, *args, **kwargs)
        return add_pattern_func
    return pattern_adder