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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 get_i_text(node):
 """ Get the text for an Indicator node. :param node: Indicator node. :return: """

        if node.tag != 'Indicator':
            raise IOCParseError('Invalid tag: {}'.format(node.tag))
        s = node.get('operator').upper()
        return s