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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 check_model(self):
 """ Check the model for various errors. This method checks for the following errors. In the same time also updates the cardinalities of all the random variables. * Checks if clique potentials are defined for all the cliques or not. * Check for running intersection property is not done explicitly over here as it done in the add_edges method. Returns ------- check: boolean True if all the checks are passed """

        if not nx.is_connected(self):
            raise ValueError('The Junction Tree defined is not fully connected.')

        return super(JunctionTree, self).check_model()