当我尝试通过终端运行pig并给出命令pig时。显示错误:16/01/2202:51:54INFOpig.ExecTypeProvider:TryingExecType:LOCAL16/01/2202:51:54INFOpig.ExecTypeProvider:TryingExecType:MAPREDUCE16/01/2202:51:54INFOpig.ExecTypeProvider:PickedMAPREDUCEastheExecType2016-01-2202:51:54,470[main]INFOorg.apache.pig.Main-ApachePigversion0.13.