The unique identifier for an entity in the Google Ads API is called a resource name, and is represented as a string with a predictable format. If you know the constituent components of a resource name, you can use this utility to generate the final resource name.
PathLookupUtil
The path lookup util is a way to construct the resource name of an entity if you
know all of the relevant IDs related to that entity. For example, a campaign
resource name is in the format
customers/{customer_id}/campaigns/{campaign_id}, so if you know the customer
ID and the campaign ID, you can use the path lookup util to construct the full
resource name as follows:
client.path.campaign(customer_id, campaign_id)
You can use other entity names as well, which take different IDs depending on the final form of the resource name.