Abaqus Python selcet two nodesets as a region

Hello Community,

I created a python script to do some calculations and create a new field for a specific region / nodeset.

I defined the region by

MyRegion= myodbfile.rootAssembly.instances['PART-1-1'].\
nodeSets['KUSA_LS2F_SURF_KUSA-KUZA']

Now I want to add a second nodeset to the region like

MyRegion= myodbfile.rootAssembly.instances['PART-1-1'].\
nodeSets['KUSA_LS2F_SURF_KUSA-KUZA', 'KUSA_LS2F']

but it does not work. How can I define multiple sets in nodeSets[]?