title: How to populate a variable based on the choice of another variable in Grafana?
body: <p>I have a dashboard which uses AWS Cloudwatch as datasource.
  I have a variable <code>Region</code> which gives me regions of AWS i.e. <code>us-east-1, us-west-2</code> etc.
  I want to create another variable called <code>RegionCode</code> which populates itself based on the selection of <code>Region</code> variable.</p>
  <p>For example: If I select <code>us-east-1</code> from <code>Region</code> dropdown, <code>RegionCode</code> variable gets populated with <code>USE1</code> and if I select <code>us-west-2</code>, it gets populated with <code>USW2</code>. I have been browsing around all over the web to look for a way but can't figure it out.</p>
  <p>Please help.</p>