def get_next_slot_iters(self, header_hash: bytes32, new_slot: bool) -> uint64:
    assert self.contains_block(header_hash)
    curr = self.block_record(header_hash)
    if (curr.height <= 2):
        return self.constants.SUB_SLOT_ITERS_STARTING
    return get_next_sub_slot_iters_and_difficulty(self.constants, new_slot, curr, self)[0]
def get_next_slot_iters(self, header_hash: bytes32, new_slot: bool) -> uint64:
    assert self.contains_block(header_hash)
    curr = self.block_record(header_hash)
    if (curr.height <= 2):
        return self.constants.SUB_SLOT_ITERS_STARTING
    return get_next_sub_slot_iters_and_difficulty(self.constants, new_slot, curr, self)[0]