title: Boto3 errors out with 'Could not connect to the endpoint URL: "https://ec2.us-west-2.amazonaws.com/"'
body: <p>I am running some python code on an AWS EC2 instance. The IAM role for this EC2 instance has adequate privileges to describe and create new EC2 instances.</p>
  
  <p>My code calls <code>ec2_client.describe_instances()</code> and checks whether a specific instance is alive. If that instance is terminated, it will call <code>ec2_client.run_instances</code> and create a new instance.</p>
  
  <p>However, when I call <code>ec2_client.run_instances()</code>, I get an error <code>Could not connect to the endpoint URL: "https://ec2.us-west-2.amazonaws.com/"</code>. </p>
  
  <p><code>ec2_client</code> is a boto3 EC2 client object.</p>
  
  <p>In some other examples, I've seen people getting this error because they had an incorrect region. That is not the case here. I've made sure that the region is correct.</p>
  
  <p>Any ideas why this happens?</p>
  
  <p>I am using <code>boto3</code> (1.4.4).</p>