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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 start(self):
 """ Try to remove the old mock logs first. """

        if self.resultdir:
            for lname in self.mock_logfiles:
                self.logfiles[lname] = self.build.path_module.join(self.resultdir,
                                                                   lname)
        else:
            for lname in self.mock_logfiles:
                self.logfiles[lname] = lname
        self.addLogObserver('state.log', MockStateObserver())

        cmd = remotecommand.RemoteCommand('rmdir', {'dir':
                                                    [self.build.path_module.join('build', self.logfiles[l])
                                                     for l in self.mock_logfiles]})
        d = self.runCommand(cmd)
        # must resolve super() outside of the callback context.
        super_ = super()

        @d.addCallback
        def removeDone(cmd):
            super_.start()
        d.addErrback(self.failed)