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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 compress(self, d=DEFAULT):
 """Returns a copy of d with compressed leaves."""

        if d is DEFAULT:
            d = self
        if isinstance(d, list):
            l = [v for v in (self.compress(v) for v in d)]
            try:
                return list(set(l))
            except TypeError:
                # list contains not hashables
                ret = []
                for i in l:
                    if i not in ret:
                        ret.append(i)
                return ret
        elif isinstance(d, type(self)):
            return type(self)({k: v for k, v in ((k, self.compress(v)) for k, v in d.items())})
        elif isinstance(d, dict):
            return {k: v for k, v in ((k, self.compress(v)) for k, v in d.items())}
        return d