docs: def river_couchdb_create(self, index_name,index_type='',couchdb_db='', river_name='',couchdb_host='localhost', couchdb_port='5984',couchdb_user=None, couchdb_password=None, couchdb_filter=None,script=''):
          '''
          https://github.com/elasticsearch/elasticsearch-river-couchdb
  
          Creates a river for the specified couchdb_db.
  
          > search = ElasticSearch()
          > search.river_couchdb_create('feeds','feeds','feeds')
            {u'_id': u'_meta',
           u'_index': u'_river',
           u'_type': u'test_db',
           u'_version': 1,
           u'ok': True}
          '''
          request = self.session
          if not index_type:
              index_type = index_name
          if not couchdb_db:
              couchdb_db = index_name
          content = {
              'type' : 'couchdb',
              'couchdb' : {
                  'host' : couchdb_host,
                  'port' : couchdb_port,
                  'db' : couchdb_db,
                  'filter' : couchdb_filter
              },
              'index' : {
                  'index' : index_name,
                  'type' : index_type
              }
          }
          if couchdb_user and couchdb_password:
              content['couchdb']['user'] = couchdb_user
              content['couchdb']['password'] = couchdb_password
          if script:
              content['couchdb']['script'] = script
          if self.verbose:
              print content
          url = 'http://%s:%s/_river/%s/_meta' %(self.host, self.port, river_name or index_name)
          response = request.post(url,content)
          return response