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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_edges(self):
 """ Returns the edges of the network. Returns ------- set: set containing the edges of the network Example ------- {('var_0', 'var_1'), ('var_0', 'var_2'), ('var_1', 'var_2')} """

        edges = []
        for function in range(0, self.no_functions):
            function_variables = self.grammar.parseString(self.network)['fun_' + str(function)]
            if isinstance(function_variables, int):
                function_variables = [function_variables]
            if self.network_type == 'BAYES':
                child_var = "var_" + str(function_variables[-1])
                function_variables = function_variables[:-1]
                for var in function_variables:
                    edges.append((child_var, "var_" + str(var)))
            elif self.network_type == "MARKOV":
                function_variables = ["var_" + str(var) for var in function_variables]
                edges.extend(list(combinations(function_variables, 2)))
        return set(edges)