to set fixed values for nuisance parameters associated with Planck CMB Data

[Meg140]

I want to constrain a value for certain cosmological parameters using the parameter file. I tested it with different observables, but it doesn't seem possible with the CMB data. This is because the nuisance parameters are a requirement in the file, and I couldn't find a function, such as 'cosmo_argument,' to fix the value and prevent any Markov chain from running.

Do you know how I can use Planck CMB just to obtain the chi-squared associated with that likelihood?