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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 readstream(self, stream):
 """ Reads the specified stream and parses the token elements generated from tokenizing the input data. `stream` ``File``-like object. Returns boolean. """


        self._reset()

        try:
            # tokenize input stream
            self._lexer = SettingLexer()
            self._lexer.readstream(stream)

            # parse tokens into AST
            self._parse()
            return True

        except IOError:
            self._reset()
            return False