title: AWS Default region not setting using env variable in boto
body: <p>Python terminal below</p>
  
  <pre><code>In [3]: os.environ['AWS_DEFAULT_REGION']
  Out[3]: 'us-west-2'
  
  In [4]: import boto
  
  In [5]: boto.connect_ec2()
  Out[5]: EC2Connection:ec2.ap-southeast-1.amazonaws.com
  </code></pre>
  
  <p>AWS Default region is not getting set even after using <code>AWS_DEFAULT_REGION</code> as env variable. Please suggest !</p>