code: def delete_servers(self, server_id):
          
          endpoint = "https://api.newrelic.com"
          uri = "{endpoint}/api/v1/accounts/{account_id}/servers/{server_id}.xml".format(
              endpoint=endpoint,
              account_id=self.account_id,
              server_id=server_id)
          response = self._make_delete_request(uri)
          failed_deletions = []
          for server in response.findall('.//server'):
              if not 'deleted' in server.findall('.//result')[0].text:
                  failed_deletions.append({'server_id': server.get('id')})
  
          return failed_deletions
docs: Requires: account ID, server ID
          Input should be server id
          Returns: list of failed deletions (if any)
          Endpoint: api.newrelic.com
          Errors: 403 Invalid API Key
          Method: Delete