Assertion error in builder.py

[graik]

I want to create a linker between a single SER residue (in its own PDB) and another domain. I received an assertion error without explanation. Assertion errors are meant to never happen so this is a bug. If this is a Pulchra or Ranch problem, it has to be converted into a proper exception with some explanation... better would of course be if single residue domains could be supported (assuming that's the problem).

Command:
multipr --chain cleaned_peptide_Nterm.pdb GSG cleaned_spyC.pdb:B --fixed cleaned_peptide_Nterm.pdb cleaned_spyC.pdb

Traceback:

  File "/home/raik/data/py/multiprot/multiprot/scripts/multipr", line 20, in <module>
    model = build.run()
  File "/data/raik/local/py/multiprot/venv/lib/python3.7/site-packages/multiprot/builder.py", line 651, in run
    self.create_full()
  File "/data/raik/local/py/multiprot/venv/lib/python3.7/site-packages/multiprot/builder.py", line 594, in create_full
    s = self.process_fullchain(chaini,model,out_symseq, bound_indexes)
  File "/data/raik/local/py/multiprot/venv/lib/python3.7/site-packages/multiprot/builder.py", line 515, in process_fullchain
    modeled_domains, chaini.args["symtemplate"], chaini.container_jdom)
  File "/data/raik/local/py/multiprot/venv/lib/python3.7/site-packages/multiprot/builder.py", line 320, in pulchra_rebuild
    symtemplate, container_jdom)
  File "/data/raik/local/py/multiprot/venv/lib/python3.7/site-packages/multiprot/builder.py", line 263, in restore_pulchra
    rdom.sequence()
AssertionError

[graik]

structures.zip