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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 visit_UnaryOperation(self, node):
 """Visitor for `UnaryOperation` AST node."""

        if node.op.nature == Nature.PLUS:
            return +self.visit(node.right)
        elif node.op.nature == Nature.MINUS:
            return -self.visit(node.right)
        elif node.op.nature == Nature.NOT:
            return Bool(not self.visit(node.right))