release 1.6.4

Author: dt3310321

setup.py

@@ -16,7 +16,7 @@ def long_description():
 
 setup(
     name='cos-python-sdk-v5',
-    version='1.6.3',
+    version='1.6.4',
     url='https://www.qcloud.com/',
     license='MIT',
     author='tiedu, lewzylu, channingliu',