code: function getKinesisOptionsUsed(region) {
    const regionKey = getRegionKey(region);
    return regionKey ? kinesisOptionsByRegionKey.get(regionKey) : undefined;
  }
docs: Gets the kinesis options used to construct the Kinesis instance cached for the given region (if specified and if
  previously cached); otherwise for the current region (if previously cached); otherwise returns undefined.
  @param {string} [region] - the optional AWS region to use - defaults to current AWS region if not specified
  @returns {AWS.Kinesis|undefined} the kinesis options used to construct the Kinesis instance cached for the given or
  current region (if any); otherwise returns undefined