I found that there is a type of id start with py_
,
It is unique id for payments,
but I have never seen it in Stripe API doc.
py_
objects have the same API shape as the Charge object. They are fundamentally the same thing, but in most cases represent a transaction/transfer between two Stripe accounts (i.e. with Connect) or non-card payment methods.
See Creating destination charges on your platform for more details.