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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 _pidExists(pid):
 """ This will return True if the process associated with pid is still running on the machine. This is based on stackoverflow question 568271. :param int pid: ID of the process to check for :return: True/False :rtype: bool """

        assert pid > 0
        try:
            os.kill(pid, 0)
        except OSError as err:
            if err.errno == errno.ESRCH:
                # ESRCH == No such process
                return False
            else:
                raise
        else:
            return True