训练自定义数据集，使用VOC数据集格式，昆虫数据集，执行命令python tools/train.py -c configs/faster_rcnn_r50_fpn_1x.yml  提示

2021-07-31 11:51:01,653 - INFO - If regularizer of a Parameter has been set by '
fluid.ParamAttr' or 'fluid.WeightNormParamAttr' already. The Regularization[L2De
cay, regularization_coeff=0.000100] in Optimizer will not take effect, and it wi
ll only be applied to other Parameters!
D:\Python\Python35\lib\site-packages\paddle\fluid\io.py:2302: UserWarning: This
list is not set, Because of Paramerter not found in program. There are: fc_0.b_0
fc_0.w_0
format(" ".join(unused_para_list)))
Traceback (most recent call last):
File "tools/train.py", line 413, in
main()
File "tools/train.py", line 246, in main
num_trainers=num_trainers)
File "E:\yxx\PaddleDetection-release-2.1\PaddleDetection-release-2.1\static\pp
det\data\reader.py", line 443, in create_reader
reader = Reader(**cfg)()
File "E:\yxx\PaddleDetection-release-2.1\PaddleDetection-release-2.1\static\pp
det\data\reader.py", line 211, in __init__
self._roidbs = self._dataset.get_roidb()
File "E:\yxx\PaddleDetection-release-2.1\PaddleDetection-release-2.1\static\pp
det\data\source\dataset.py", line 68, in get_roidb
self.load_roidb_and_cname2cid()
File "E:\yxx\PaddleDetection-release-2.1\PaddleDetection-release-2.1\static\pp
det\data\source\voc.py", line 155, in load_roidb_and_cname2cid
gt_class.append([cname2cid[cname]])
KeyError: 'a'

其中的“a”,是Annotations xml文件，自定义的名称

如下：
a
Unspecified
0
0

628
482
728
569

使用labelImg 工具自动生成的xml文件，请问下，这个问题怎么解决一下？