'Retrieve the field data stats for one or more indices
(See :ref:\'es-guide-reference-api-admin-cluster-nodes-stats\')
:keyword indices: an index or a list of indices'

def field_stats(self, indices=''):

    path = self.conn._make_path(indices, (), '_stats', 'fielddata')
    return self.conn._send_request('GET', path)
