title: S3 authentication via EC2 without passing AWS Access Key & Secret key in code or storage
body: <p>I am trying to access S3 buckets via EC2 machine using python SDK(Boto).
  I know we can do by IAM roles by using its access key and secret key. We can use it by hardcoding in code or store it in config file on EC2 local storage.
  I know we can create a policy and role and assign to EC2 machine</p>
  
  <p>But is there any another way without putting access key and secret key in python program or ec2 storage we can access S3 bucket or any AWS resources?</p>
  
  <p>My motto is I have to access aws resources via python program without using access key and secret key and secure my access key and secret key.</p>