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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 set_scroll_offset(editor, value):
 """ Set scroll offset. """

    if value is None:
        editor.show_message('scrolloff=%i' % editor.scroll_offset)
    else:
        try:
            value = int(value)
            if value >= 0:
                editor.scroll_offset = value
            else:
                editor.show_message('Argument must be positive')
        except ValueError:
            editor.show_message('Number required after =')