AttributeError: InteractionType instance has no attribute '__getitem__'

[anitaknivedha]

I am running into the following error upon running psf2top.py using Python ver. 2.7.13.

Command: psf2top.py -p system.psf -c toppar/par_all36m_prot.prm toppar/liga_hyd.par toppar/par_wation.par -v

mainapp - DEBUG - >> started main
mainapp.psf.PSFSystem - DEBUG - >> entering PSFSystem
mainapp.psf.PSFSystem - DEBUG - parsing psf file: system.psf
mainapp.psf.PSFSystem - WARNING - could not find NAMD keywork in the first line in the psf file
mainapp.psf.PSFSystem - DEBUG - skipping section: '3 !NTITLE'
mainapp.psf.PSFSystem - DEBUG - skipping section: '592 !NDON: donors'
mainapp.psf.PSFSystem - DEBUG - skipping section: '509 !NACC: acceptors'
mainapp.psf.PSFSystem - DEBUG - skipping section: '0 !NNB'
mainapp.psf.PSFSystem - DEBUG - skipping section: '1591 0 !NGRP NST2'
mainapp.psf.PSFSystem - DEBUG - skipping section: '1 !MOLNT'
mainapp.psf.PSFSystem - DEBUG - skipping section: '0 0 !NUMLP NUMLPH'
mainapp.psf.PSFSystem - DEBUG - parsing took 0.6 seconds
mainapp.psf.PSFSystem - DEBUG - << leaving PSFSystem
mainapp.psf.PSFSystem - DEBUG - converting psf to multiple molecules based on chains
mainapp.charmmpar.CharmmPar - DEBUG - >> entering CharmmPar
mainapp.charmmpar.CharmmPar - DEBUG - parsing parameter file: toppar/par_all36m_prot.prm
mainapp.charmmpar.CharmmPar - DEBUG - parsing took 0.0 seconds
mainapp.charmmpar.CharmmPar - DEBUG - 132 bonding, 364 angle, 550 dih, 35 imp, 53 nonbonding and 6 cmaps
mainapp.charmmpar.CharmmPar - DEBUG - parsing parameter file: toppar/liga_hyd.par
mainapp.charmmpar.CharmmPar - DEBUG - parsing took 0.0 seconds
mainapp.charmmpar.CharmmPar - DEBUG - 142 bonding, 386 angle, 587 dih, 56 imp, 60 nonbonding and 6 cmaps
mainapp.charmmpar.CharmmPar - DEBUG - parsing parameter file: toppar/par_wation.par
mainapp.charmmpar.CharmmPar - DEBUG - parsing took 0.0 seconds
mainapp.charmmpar.CharmmPar - DEBUG - 145 bonding, 387 angle, 587 dih, 56 imp, 75 nonbonding and 6 cmaps
mainapp.charmmpar.CharmmPar - DEBUG - << leaving CharmmPar
mainapp.charmmpar.CharmmPar - DEBUG - adding parameters to the system...
adding pair param to the mol for POT-CLA
adding pair param to the mol for NC2-OC
adding pair param to the mol for SOD-CLA
mainapp.grotop.SystemToGroTop - DEBUG - >> entering SystemToGroTop
mainapp.grotop.SystemToGroTop - DEBUG - starting to assemble topology...
mainapp.grotop.SystemToGroTop - DEBUG - making atom/pair/bond/angle/dihedral/improper types
Traceback (most recent call last):
File "/projects/Common/PYTHON/Python-2.7.13/bin/psf2top.py", line 107, in
main()
File "/projects/Common/PYTHON/Python-2.7.13/bin/psf2top.py", line 99, in main
grotop.SystemToGroTop(psfsys)
File "/projects/Common/PYTHON/Python-2.7.13/lib/python2.7/site-packages/pytopol/parsers/grotop.py", line 662, in init
self.assemble_topology()
File "/projects/Common/PYTHON/Python-2.7.13/lib/python2.7/site-packages/pytopol/parsers/grotop.py", line 691, in assemble_topology
top = top.replace('PAIRTYPES', ''.join( self._make_pairtypes(self.system)) )
File "/projects/Common/PYTHON/Python-2.7.13/lib/python2.7/site-packages/pytopol/parsers/grotop.py", line 801, in _make_pairtypes
e14 = inter_at_types[(at2,at1)]['param']['lje']
AttributeError: InteractionType instance has no attribute 'getitem'

Could you please help me with fixing this?

Thanks!
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