$ aws login
Username [username]: pea1
Password: ********
Factor:
$ aws login
Password: 
Factor: push
Please choose the role you would like to assume:
     Account: 000011112222
         [ 0 ]: shib-cs
     Account: 777788889999
         [ 1 ]: shib-admin
         [ 2 ]: shib-cs
         [ 3 ]: shib-dba
Selection: 1
$ aws sts get-caller-identity
{
    "UserId": "AROAICCPMY7VALLFYHWPA:pea1@cornell.edu",
    "Account": "777788889999",
    "Arn": "arn:aws:sts::777788889999:assumed-role/shib-admin/pea1@cornell.edu"
}