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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 increment_lineno(node, n=1):
 """ Increment the line numbers of all nodes by `n` if they have line number attributes. This is useful to "move code" to a different location in a file. """

    for node in zip((node,), walk(node)):
        if 'lineno' in node._attributes:
            node.lineno = getattr(node, 'lineno', 0) + n