Update app.py to stop download checkpoints/ocr_general_clean.pt if we already downloaded the file

app.py

@@ -25,8 +25,9 @@ import gradio as gr
 # Register refcoco task
 tasks.register_task('ocr', OcrTask)
 
-os.system('wget https://shuangqing-multimodal.oss-cn-zhangjiakou.aliyuncs.com/ocr_general_clean.pt; '
-          'mkdir -p checkpoints; mv ocr_general_clean.pt checkpoints/ocr_general_clean.pt')
+if not os.path.exists("checkpoints/ocr_general_clean.pt"):
+    os.system('wget https://shuangqing-multimodal.oss-cn-zhangjiakou.aliyuncs.com/ocr_general_clean.pt; '
+              'mkdir -p checkpoints; mv ocr_general_clean.pt checkpoints/ocr_general_clean.pt')
 
 # turn on cuda if GPU is available
 use_cuda = torch.cuda.is_available()