John The Ripper and PBKDF2-HMAC-SHA1

I am trying to hash a list of passwords with PBKDF2-HMAC-SHA1 and then crack them using John. However, John does not recognise the hashes and I get a No Hashes Found error. It works with SHA256, but I need PBKDF2-HMAC-SHA1. I have looked everywhere and have exhausted all my options. What is the correct format of PBKDF2-HMAC-SHA1 that is recognised by John and will let me crack it? Thanks in advance!