Confusing instructions on the ticket for migration

I have got a ticket asking me to do the following:

As part of the above notice we are moving to a new database platform towards the end of October. To ensure successful migration of the app, we need your support with a few things:

We would need you to implement a function with this signature

function (item)

So in practice it would look like

function (item) {
  delete item.longValue
  return item

Where should I implement it? A function without a name? What is the impact if not implemented? Has this been reviewed by an Atlassian developer at all?