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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 find_undeclared(nodes, names):
 """Check if the names passed are accessed undeclared. The return value is a set of all the undeclared names from the sequence of names found. """

    visitor = UndeclaredNameVisitor(names)
    try:
        for node in nodes:
            visitor.visit(node)
    except VisitorExit:
        pass
    return visitor.undeclared