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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 is_clique(self, nodes):
 """ Check if the given nodes form a clique. Parameters nodes: list, array-like List of nodes to check if they are a part of any clique. Examples -------- ('B', 'E'), ('D', 'E'), ('E', 'F'), ('D', 'F'), ('B', 'F')]) False True Since B, D, E and F are clique, any subset of these should also be clique. True """

        for node1, node2 in itertools.combinations(nodes, 2):
            if not self.has_edge(node1, node2):
                return False
        return True