MDM Record can be in that checkout Statuses:
Record.CheckoutStatus.UNDEFINED: -1
Record.CheckoutStatus.NONE: 0 - record is not checked out
Record.CheckoutStatus.ORIGINAL: 1 - you found original record, that means record is checked out and you found protected version of record.
Record.CheckoutStatus.MEMBER: 2 - record is checked out and you joined to checkout and you found record which is checked out, not protected version.
Record.CheckoutStatus.OWNER: 3 - record is checked out and you owner of the chekced out version, and you found checked out version, not protected version.
Record.CheckoutStatus.NON_MEMBER: 4 - record is checked out and you did not join, and you found checked out version, not protected version.