can you attach the 3dm file you are trying to read?
also you can format the code using codeblocks
import Rhino as r
f=r.FileIO.File3dm.Read(x)
o=f.Objects
values = []
a=[i.Attributes.GetUserStrings().AllKeys for i in o]
for key,objs in zip(a,o):
v= objs.Attributes.GetUserStrings().Get(key)[0]
values.append(v)
b=values