LookalikeUserlist, composed of users similar to those of a configurable seed (set of UserLists)

[Proto definition ![GitHub](https://developers.google.com/site-assets/logo-github.svg)](https://github.com/googleapis/googleapis/blob/master/google/ads/googleads/v26/common/user_lists.proto)

| Fields ||
|---|---|
| ## `country_codes[]` | `string` Countries targeted by the Lookalike. Two-letter country code as defined by ISO-3166 |
| ## `expansion_level` | `https://developers.google.com/google-ads/api/reference/rpc/v26/LookalikeExpansionLevelEnum.LookalikeExpansionLevel` Expansion level, reflecting the size of the lookalike audience |
| ## `seed_user_list_ids[]` | `int64` Seed UserList ID from which this list is derived, provided by user. |