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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 getCommandLine(self):
 """Insert the precursor and change directory commands """

        commandLine = self.precursor + self.sep if self.precursor else ''
        commandLine += self.cd + ' ' + self.path + self.sep if self.path else ''
        commandLine += PosixCommand.getCommandLine(self)
        return commandLine