更新 'gpu_mnist_example/train_gpu.py'

gpu_mnist_example/train_gpu.py

@@ -12,7 +12,6 @@ If there are Chinese comments in the code，please add at the beginning：
 
 '''
 import os
-os.system("pip cache purge")
 os.system("pip install {}".format(os.getenv("OPENI_SDK_PATH")))
 
 from model import Model