It's like sudo, but for aws commands:
cbrown@mbp:~% aws s3 ls
An error occurred (AccessDenied) when calling the ListBuckets operation: Access Denied
cbrown@mbp:~% mfado aws s3 ls
MFA Code: 123456
2017-04-30 19:08:05 my-cloudtrail-bucket
2017-04-30 19:11:29 my-other-bucket
Install with pip: pip install https://github.com/ccbrown/mfado/archive/master.zip