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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 add_block(self, nodes, data):
 """Adds a new check node and edges between that node and all source nodes it connects, resolving all message passes that become possible as a result. """


        # We can eliminate this source node
        if len(nodes) == 1:
            to_eliminate = list(self.eliminate(next(iter(nodes)), data))

            # Recursively eliminate all nodes that can now be resolved
            while len(to_eliminate):
                other, check = to_eliminate.pop()
                to_eliminate.extend(self.eliminate(other, check))
        else:

            # Pass messages from already-resolved source nodes
            for node in list(nodes):
                if node in self.eliminated:
                    nodes.remove(node)
                    data ^= self.eliminated[node]

            # Resolve if we are left with a single non-resolved source node
            if len(nodes) == 1:
                return self.add_block(nodes, data)
            else:

                # Add edges for all remaining nodes to this check
                check = CheckNode(nodes, data)
                for node in nodes:
                    self.checks[node].append(check)

        # Are we done yet?
        return len(self.eliminated) >= self.num_blocks