Add WooCommerce Membership Automatically to New User Signups via Gravity Forms

Guys, We are using Gravity Forms to allow users to signup for an account on our website (using the Gravity Forms User Signup add-on) - we need a custom function written so that ANY users who signup for an account via this Gravity Forms form, automatically get a specific Membership added to their account. We use WooCommerce Memberships so the membership would be one by that plugin. We have found this article online along with some code that is doing ALMOST exactly what we want. Theirs signs the user up to a free trial of a specific membership. We don't need or want the trial. We simply want the membership added to their account. [login to view URL] I have already created the user signup form - it works perfectly. You can see that at this link: [login to view URL] The ONLY part of this job that I need your input on is automatically adding a specific membership to the new user signups. The membership should ONLY be automatically applied to accounts signed up via this Gravity form. We don't want it to add on for all accounts that might sign up via WooCommerce etc. Need work done ASAP.