Yii2 and Amazon AWS S3 how to create such methods?

Question

Yii

Hello, I'm asking for help, tell me or show me how to do this task: Create 2 methods
getContent($bucket, $filename) - get the file content from the specified bucket along the path /
setContent($bucket, $filename, $content) - save the file content in specified bucket on path /
Describe bucket names as constants in class
use https://github.com/frostealth/yii2-aws-s3