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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 get_filter_fields(self, exclude=None):
 """ Get the fields that are normal filter fields """


        exclude_set = set(self.exclude)
        if exclude:
            exclude_set = exclude_set.union(set(exclude))

        return [name for name in self.fields
                if name not in exclude_set]