~/.aws/config:
[profile account1]
region = us-east-1
output = json

[profile account2]
region = us-east-1
output = json
role_arn = arn:aws:iam::<account1_number>:role/<role_name>
source_profile = account1


~/.aws/credentials:
[account1]
aws_secret_access_key = <account1_iam_access_key>

[account2]
role_arn       = arn:aws:iam::<account1_number>:role/<role_name>
source_profile = account1