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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 diropenbox(msg=None , title=None , default=None ):
 """ A dialog to get a directory name. Note that the msg argument, if specified, is ignored. Returns the name of a directory, or None if user chose to cancel. If the "default" argument specifies a directory name, and that directory exists, then the dialog box will start with that directory. """

    if sys.platform == 'darwin':
        _bring_to_front()
    title=getFileDialogTitle(msg,title)
    localRoot = Tk()
    localRoot.withdraw()
    if not default: default = None
    f = tk_FileDialog.askdirectory(
          parent=localRoot
        , title=title
        , initialdir=default
        , initialfile=None
        )
    localRoot.destroy()
    if not f: return None
    return os.path.normpath(f)