What is the variable name for a second light entity?

[kuro6]

According to v2.0.0, custom card room supports two light entities. What is the variable name for the second light entity? In other words, what would I replace the question marks below with so that I have two light entities displayed on the card? Thanks.

variables:
  ulm_custom_card_esh_room_light_entity: light.lights1
  ???????: light.lights2

Copy of changelog 2.0.0: Breaking changes! This change introduces two variables to allow the display of the card with no buttons, one for light, one for climate or both for light and climate. It also now allows the use of no entity at all.