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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 dovc(self, cmd):
 """This accepts the arguments of a command, without the actual command itself."""

        env = os.environ.copy()
        env['LC_ALL'] = "C"
        d = utils.getProcessOutputAndValue(self.exe, cmd, env=env,
                                           path=self.treetop)
        d.addCallback(self._didvc, cmd)
        return d