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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 add_task(self, pid):
 """ Add a process to the cgroups represented by this instance. """

        _register_process_with_cgrulesengd(pid)
        for cgroup in self.paths:
            with open(os.path.join(cgroup, 'tasks'), 'w') as tasksFile:
                tasksFile.write(str(pid))