我已经为此苦苦挣扎了很长时间-defaws_file_exists?filenamebegin@s3_interface.get('bucket',filename)returntruecatchAws::AwsError,Aws::AwsError2,NoSuchKey,RuntimeError,AmazonError,AWSErrorreturnfalseendend只是，它没有捕捉到!(@^%@&$*%#错误，报告为:Aws::AwsError:NoSuchKey:Thespecifiedkeydoesnotexist.我做错了什么/我需要捕获的错误类型是什么？