code: def delete_instance(credentials, project, zone, name, wait_until_done=False):
      
  
      access_token = credentials.get_access_token()
  
      headers = {
          'Authorization': 'Bearer %s' % access_token.access_token
      }
  
      r = requests.delete('https://www.googleapis.com/compute/v1/'
                          'projects/%s/zones/%s/instances/%s'
                          % (project, zone, name),
                          headers=headers)
  
      r.raise_for_status()
  
      op_name = r.json()['name']
  
      _LOGGER.info('Submitted request to create intsance '
                  '(HTTP code: %d).',
                  r.status_code)
  
      if wait_until_done:
          _LOGGER.info('Waiting until operation is done...')
          wait_for_zone_op(access_token, project, zone, op_name)
  
      return op_name
docs: Delete an instance.
  
      TODO: docstring