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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_search_fields(cls):
 """ Returns search fields in sfdict """

        sfdict = {}
        for klass in tuple(cls.__bases__) + (cls, ):
            if hasattr(klass, 'search_fields'):
                sfdict.update(klass.search_fields)
        return sfdict