fix py3.6 bug

paddlex/ppdet/engine/tracker.py

@@ -29,7 +29,7 @@ from paddlex.ppdet.modeling.mot.utils import Timer, load_det_results
 from paddlex.ppdet.modeling.mot import visualization as mot_vis
 
 from paddlex.ppdet.metrics import Metric, MOTMetric, KITTIMOTMetric
-import paddlex.ppdet.utils.stats as stats
+from paddlex.ppdet.utils import stats
 
 from .callbacks import Callback, ComposeCallback
 

paddlex/ppdet/engine/trainer.py

@@ -37,7 +37,7 @@ from paddlex.ppdet.utils.visualizer import visualize_results, save_result
 from paddlex.ppdet.metrics import Metric, COCOMetric, VOCMetric, WiderFaceMetric, get_infer_results, KeyPointTopDownCOCOEval, KeyPointTopDownMPIIEval
 from paddlex.ppdet.metrics import RBoxMetric, JDEDetMetric
 from paddlex.ppdet.data.source.category import get_categories
-import paddlex.ppdet.utils.stats as stats
+from paddlex.ppdet.utils import stats
 
 from .callbacks import Callback, ComposeCallback, LogPrinter, Checkpointer, WiferFaceEval, VisualDLWriter
 from .export_utils import _dump_infer_config