我正在使用 python 进行 ibm 云对象存储，我使用 ibm-cos-sdk 库建立连接并执行以下操作
-> Creating Bucket
-> List Created Buckets
-> Uploading data init
But i am unable to download contents form the bucket
s3.download_file(Filename=filename, Bucket=bucket, Key=objectname)
I am uisng download_file function, getting client error
I am new to ibm cloud.