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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 keyword(self, token_stream, token, operators):
 """Lowest level parsing function. A keyword consists of zero or more prefix operators (NOT, or COMPARISON) followed by a TEXT, COLOR, or NUMBER block. """

        if token[0] == 'TEXT' or token[0] == 'COLOR':
            return SearchKeyword(token[1], **operators)
        elif token[0] == 'COMPARISON':
            operators['comparison'] = token[1]
        elif token[0] == 'NOT':
            operators['boolean'] = 'not'
        else:
            if token[1] == None:
                problem = 'end of input.'
            else:
                problem = 'token {0} in input'.format(token[1])
            raise SyntaxError('Unexpected {0}'.format(problem))
        token = next(token_stream)
        return self.keyword(token_stream, token, operators)