Hi Raghav,
There is a function pvlib.iotools.read_panond that will read either a PAN or OND file and return a dict of its content. That content is not translated to pvlib variable names; that translation is up to the user. PVsyst's documentation isn't sufficiently clear to explain all the steps involved from reading a PAN or OND file, to assigning parameters for the models.
More broadly, you can certainly import custom inverter and module parameters for use in pvlib. There are functions in pvlib.ivtools to help to get parameters from, e.g., a module datasheet.
Best regards,
Cliff