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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 clean_empty(self, d=DEFAULT):
 """Returns a copy of d without empty leaves. https://stackoverflow.com/questions/27973988/python-how-to-remove-all-empty-fields-in-a-nested-dict/35263074 """

        if d is DEFAULT:
            d = self
        if isinstance(d, list):
            return [v for v in (self.clean_empty(v) for v in d) if v or v == 0]
        elif isinstance(d, type(self)):
            return type(self)({k: v for k, v in ((k, self.clean_empty(v)) for k, v in d.items()) if v or v == 0})
        elif isinstance(d, dict):
            return {k: v for k, v in ((k, self.clean_empty(v)) for k, v in d.items()) if v or v == 0}
        return d