Script running, but returns no results

Hi,
Sorry for this duplicated topic. I posted it to the wrong place (PyRosetta Script) I think.

I wrote a simple script to calculate the free energy. The PyRosetta was successfully initiated, but returned me nothing.
This is my script:

import rosetta
rosetta.init()
import sys

def deltaG(interface):
comp = rosetta.pose_from_pdb(interface)

f = rosetta.ScoreFunction()
f.set_weight(fa_atr,0.59)
f.set_weight(fa_rep,0.05)
f.set_weight(hbond_bb_sc,1)
f.set_weight(hbond_sc,1)
f.set_weight(fa_sol,0.37)
f.set_weight(p_aa_pp,0.29)
f.set_weight(ref,0.48)

print "delta G:", f(comp)
print f.show(comp)

def main():
interface = sys.argv[1]
deltaG(interface)

if __name__ == '__name__':
main()

And the output is:

PYROSETTA_DATABASE environment variable was set to: /home/sutr0003/software/rosetta/PyRosetta.ScientificLinux-r55194.64Bit/rosetta_database; using it....
PyRosetta 3.4.0 [Rosetta-3.4 failed_to_get_id:failed_to_get_id:73188ceda9e170d139244d5ac40f42e4fa7a9520] retrieved from:
(C) Copyright Rosetta Commons Member Institutions.
Created in JHU by Sergey Lyskov and PyRosetta Team.

core.init: Mini-Rosetta version from
core.init: command: app -database /home/sutr0003/software/rosetta/PyRosetta.ScientificLinux-r55194.64Bit/rosetta_database -ex1 -ex2aro
core.init: 'RNG device' seed mode, using '/dev/urandom', seed=-1198986531 seed_offset=0 real_seed=-1198986531
core.init.random: RandomGenerator:init: Normal mode, seed=-1198986531 RG_type=mt19937

Could you please help? Im very new to PyRosetta.
Thanks,
Chinh