I'm attempting to write a chimera script to automate the process of calculating the relative exposure of residues as per this tutorial: https://www.cgl.ucsf.edu/chimera/docs/UsersGuide/surfnorm.html

The script I have is as follows:

rc('surface') #   defines areaSES of residues rc('defattr C:/Users/Admin/Downloads/areaSESgxg.txt log 0') # define attribute using areaSESgxg.txt
for m in chimera.openModels.list(modelTypes=[chimera.Molecule]):
    for r in m.residues:
        r.relSESA = r.areaSES/ r.areaSESgxg

However, when I run this script, I am receiving this error:

When I run the process using the UI I can successfully calculate relSESA

By using the command: "surface"

Then using the assign attribute function to assign areaSESgxg.txt

Followed by using the calculate attribute function to calculate per residue: residue.areaSES/ residue.areaSESgxg

Could you advise on any methods I could use to fix this script to produce the output I am receiving from the UI.

Kind regards,

David