'Returns unicode string that represents the tree structure of
the HTML/XML documents. Only tag names are considered.
@returns: tuple of two unicode strings'

def mappedTrees(self, doc1, doc2):

    tagToCharMap = self.tagNameToCharMap(doc1, doc2, 42)
    return (self.mapTree(doc1, tagToCharMap), self.mapTree(doc2, tagToCharMap))
