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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 extend( self, itemseq ):
 """ Add sequence of elements to end of ParseResults list of elements. Example:: patt = OneOrMore(Word(alphas)) # use a parse action to append the reverse of the matched strings, to make a palindrome def make_palindrome(tokens):
 tokens.extend(reversed([t[::-1] for t in tokens])) return ''.join(tokens) print(patt.addParseAction(make_palindrome).parseString("lskdj sdlkjf lksd")) # -> 'lskdjsdlkjflksddsklfjkldsjdksl' """

        if isinstance(itemseq, ParseResults):
            self += itemseq
        else:
            self.__toklist.extend(itemseq)