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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 on_listcomp(self, node):
 # ('elt', 'generators') """List comprehension."""

        out = []
        for tnode in node.generators:
            if tnode.__class__ == ast.comprehension:
                for val in self.run(tnode.iter):
                    self.node_assign(tnode.target, val)
                    add = True
                    for cond in tnode.ifs:
                        add = add and self.run(cond)
                    if add:
                        out.append(self.run(node.elt))
        return out