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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 root(self):
 """ Reset all nodes and branches to 'root'. """

            str_treeRoot                = '/'
            self.l_cwd                  = [str_treeRoot]
            self.snode_current          = self.snode_root
            self.sbranch_current        = self.sbranch_root