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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 junk_folder(self):
 """ Shortcut to get Junk Folder instance :rtype: mailbox.Folder """

        return self.folder_constructor(parent=self, name='Junk',
                                       folder_id=OutlookWellKnowFolderNames
                                       .JUNK.value)