code: def delete_existing_policy(self, scaling_policy, server_group):
          
          self.log.info("Deleting policy %s on %s", scaling_policy['policyName'], server_group)
          delete_dict = {
              "application":
              self.app,
              "description":
              "Delete scaling policy",
              "job": [{
                  "policyName": scaling_policy['policyName'],
                  "serverGroupName": server_group,
                  "credentials": self.env,
                  "region": self.region,
                  "provider": "aws",
                  "type": "deleteScalingPolicy",
                  "user": "foremast-autoscaling-policy"
              }]
          }
          wait_for_task(json.dumps(delete_dict))
docs: Given a scaling_policy and server_group, deletes the existing scaling_policy.
          Scaling policies need to be deleted instead of upserted for consistency.
  
          Args:
              scaling_policy (json): the scaling_policy json from Spinnaker that should be deleted
              server_group (str): the affected server_group