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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 criteria_text(self, sep=' ', params=False):
 """ Get a text representation of the criteria node. :param sep: Separator used to indent the contents of the node. :param params: Boolean, set to True in order to display node parameters. :return: """


        s = ''
        criteria_node = self.root.find('criteria')
        if criteria_node is None:
            return s
        node_texts = []
        for node in criteria_node.getchildren():
            nt = self.get_node_text(node, depth=0, sep=sep, params=params)
            node_texts.append(nt)
        s = '\n'.join(node_texts)
        return s