To make using the Ec2 class easier to use there are two static methods that can be
invoked from any of the Ec2 Elements. The first static method is setKeys
which will defind you AWS Access Keys as default keys. When you then
create any new object you don't need to pass in any keys to the constructor.
Example 699. setKeys() Example
<?php
Zend_Service_Amazon_Ec2_Ebs::setKeys('aws_key','aws_secret_key');
To set the region that you are working in you can call the setRegion to set
which Amazon Ec2 Region you are working in. Currently there is only two region available
us-east-1 and eu-west-1. If an invalid value is passed it will throw an exception
stating that.