@abstractmethod<EOL><INDENT>def get_pid(self, unique_id, configs=None):<DEDENT>
pass<EOL>
Gets the pid of the process with `unique_id`.  If the deployer does not know of a process
        with `unique_id` then it should return a value of constants.PROCESS_NOT_RUNNING_PID
        If no pid_file/pid_keyword is specified
        a generic grep of ps aux command is executed on remote machine based on process parameters
        which may not be reliable if more process are running with similar name

        :Parameter unique_id: the name of the process