modify export air and ckpt file authority

mindspore/ccsrc/transform/graph_ir/convert.cc

@@ -1880,6 +1880,8 @@ void DfGraphConvertor::SaveParamFormat(const CNodePtr node) {
           } else {
             CheckAndConvertUtils::GetFormatStringVal(prim, &format);
           }
+        } else if (attr.second->isa<StringImm>()) {
+          format = attr.second->ToString();
         }
         if (format != "NCDHW" && format != "NHWC") {
           break;

mindspore/python/mindspore/train/callback/_loss_monitor.py

@@ -31,7 +31,7 @@ class LossMonitor(Callback):
 
     Args:
         per_print_times (int): How many steps to print once loss. During sink mode, it will print loss in the
-        nearest step. Default: 1.
+                               nearest step. Default: 1.
 
     Raises:
         ValueError: If per_print_times is not an integer or less than zero.

mindspore/python/mindspore/train/serialization.py

@@ -160,6 +160,7 @@ def _exec_save(ckpt_file_name, data_list, enc_key=None, enc_mode="AES-GCM"):
     try:
         with _ckpt_mutex:
             if os.path.exists(ckpt_file_name):
+                os.chmod(ckpt_file_name, stat.S_IWUSR)
                 os.remove(ckpt_file_name)
             with open(ckpt_file_name, "ab") as f:
                 if enc_key is not None: