Hello,

I am using s3cmd and after debugging I noticed that s3cmd does not take into account the environment variable AWS_STS_REGIONAL_ENDPOINTS.
https://docs.aws.amazon.com/sdkref/latest/guide/setting-global-sts_regional_endpoints.html

The regional endpoint for STS is used in settings where we want to use instance roles but have no access to the global endpoint sts.amazonaws.com.

I have opened an MR #1227 to fix this.

Thanks in advance for your help and feedback on the MR.