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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 comma_separated_list(self, node, subnodes):
 """Process comma separated list """

        for item in subnodes:
            position = (item.last_line, item.last_col)
            first, last = find_next_comma(self.lcode, position)
            if first:  # comma exists
                node.op_pos.append(NodeWithPosition(last, first))