docs: def list_instances(
          deployment_name='',
          cloud_name='EC2 us-east-1',
          view='tiny',
          ):
      """
      Returns a list of instances from your account.
  
      :param str deployment_name: If provided, only lists servers in the
          specified deployment.
  
      :param str cloud_name: The friendly name for a RightScale-supported cloud.
          E.g. ``EC2 us-east-1``, ``us-west-2``, etc...
  
      :param str view: The level of detail to request of RightScale.  Valid
          values are ``default``, ``extended``, ``full``, ``full_inputs_2_0``,
          ``tiny``.  Defaults to ``tiny``.
  
      """
      api = get_api()
      cloud = find_by_name(api.clouds, cloud_name)
      filters = ['state==operational']
      if deployment_name:
          deploy = find_by_name(api.deployments, deployment_name)
          filters.append('deployment_href==' + deploy.href)
      params = {'filter[]': filters, 'view': view}
      return cloud.instances.index(params=params)