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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 attributes(self, filter=Filter()):
 """ Get only the attribute content. @param filter: A filter to constrain the result. @type filter: L{Filter} @return: A list of tuples (attr, ancestry) @rtype: [(L{SchemaObject}, [L{SchemaObject},..]),..] """

        result = []
        for child, ancestry in self:
            if child.isattr() and child in filter:
                result.append((child, ancestry))
        return result