Created by: littlepan0413

如题：修改了ernie的代码，调试过程中发现错误，但是错误信息无法定位到错误代码位置

share_vars_from is set, scope is ignored.
I0910 11:16:58.119014  6704 parallel_executor.cc:329] The number of CUDAPlace, which is used in ParallelExecutor, is 1. And the Program will be copied 1 copies
I0910 11:16:58.132833  6704 build_strategy.cc:340] SeqOnlyAllReduceOps:0, num_trainers:1
example.label 1
Exception in thread Thread-1:
Traceback (most recent call last):
  File "/home/work/anaconda2/envs/paddle_gpu/lib/python2.7/threading.py", line 801, in __bootstrap_inner
    self.run()
  File "/home/work/anaconda2/envs/paddle_gpu/lib/python2.7/threading.py", line 754, in run
    self.__target(*self.__args, **self.__kwargs)
  File "/home/work/anaconda2/envs/paddle_gpu/lib/python2.7/site-packages/paddle/fluid/layers/io.py", line 593, in __provider_thread__
    raise ex
KeyError: u'1'

求问，如何设置才能正确打印错误信息的代码位置