How do I migrate content from old a reference list to another in contentful?

Question

I have a content type ("group") in contentful, that contains an Array ("link_list"). link_list accepts multiple entries of content type old_linkNow I am wondering, since I have a list of old_links with it's content, how do I take each entry of the list and convert it to the new content type new_link?

I've created a new field already: new_link_list, but how do I copy the content of each element from link_list to new_link_list?

old_link and new_link are not exactly the same, but share two fields ('slug', 'linktext') which is the content I want to be copied.

Thanks!