narrow-pars-to-dict.py

def my_pars_to_dict(p_name):
    # create empty par_dict with input name as the preset_name value
    par_dict = {
        "preset_name"   : p_name,
        "preset_vals"   : {
            "Blacklevel"     : op('base1').par.Blacklevel.val,
            "Contrast"       : op('base1').par.Contrast.val,
            "Opacity"        : op('base1').par.Opacity.val
        }
    }

    return par_dict

# example use
p_name      = "Preset001"

presets = my_pars_to_dict(p_name)
print(presets)