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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 terminate(self, pid):
 """Terminate a process bound to this context. When a process is terminated, all the processes to which it is linked will be have their ``exited`` methods called. Messages to this process will no longer be delivered. This method returns immediately. :param pid: The pid of the process to terminate. :type pid: :class:`PID` :returns: Nothing """

    self._assert_started()

    log.info('Terminating %s' % pid)
    process = self._processes.pop(pid, None)
    if process:
      log.info('Unmounting %s' % process)
      self.http.unmount_process(process)
    self.__erase_link(pid)