How to make a reservation with different core counts per node?

[mrvn]

In https://slurm.schedmd.com/reservations.html there is an example of a reservation with different core counts per node:

# Create a reservation for user brenda with two cores on
# node tux8 and 4 cores on node tux9
$ scontrol create reservation StartTime=now Duration=60 \
  Nodes=tux8,tux9 CoreCnt=2,4 User=brenda

But in pyslurm the Reservation class seems to only have an integer for cpus given the total number of cores the reservation will reserve. How do I create a Reservation instance in pyslurm for the above example?