code: function _getStrategyGrouping(_class) {
  
    return function () {
  
      var replicationParams = _.toArray(arguments)
        , replication = {"class": _class};
  
      if (_class === methods.withSimpleStrategy.name) {
        if (typeof replicationParams[0] === "undefined")
          throw new Error("SimpleStrategy requires replication parameters.");
  
        replication.replication_factor = replicationParams[0];
      }
      else if (_class === methods.withNetworkTopologyStrategy.name) {
  
        var filter = function (param) {
          return typeof param === "object" && Object.keys(param).length >= 1;
        };
        var dataCenterParams = _.filter(arguments, filter);
        if (!dataCenterParams.length)
          throw new Error("NetworkTopologyStrategy requires a variable length argument list of data center param objecs => '{ dataCenterName: dataCenterReplicationFactor }'.");
  
        _.each(dataCenterParams, function (dataCenterParam) {
          _.each(Object.keys(dataCenterParam), function (k) {
            replication[k] = dataCenterParam[k];
          });
        });
      }
  
      this._statements.push({
        grouping: "strategy",
        type: methods[nameToCallMap[_class]].name,
        value: replication
      });
  
      return this;
    };
  }
docs: Returns function used to build the `with replication` clause in a create keyspace statement
  
  @param _class
  @returns {Function}
  @private