Using "trim_inverse" to specific epitope in Antigen for complex building, errored out.

Expected Behavior

AlphaFold2_advanced.ipynb
A:B:C = VH:VL:Antigen = 1:1:1
trim_inverse(checked), trim:A1-A(#end),B1-B(#end),C(#x)-C(#y)
(#end)=last residue number; C(#x)-C(#y)=specified epitope in Antigen
##The purpose is to narrow down the complex binding surface to epitope region.

Current Behavior

##errored. program stopped. no results. error message below:
”
KeyError Traceback (most recent call last)
<ipython-input--***********> in ()
11 #@markdown - qid minimum sequence identity with query (%)
12
---> 13 mod_I = cf_af.prep_filter(I, trim, trim_inverse, cov, qid)
14
15 if I["msas"] != mod_I["msas"]:

1 frames
/content/colabfold_alphafold.py in prep_filter(I, trim, trim_inverse, cov, qid, verbose)
504 if trim != "":
505 mod_I.update(trim_inputs(trim, mod_I["msas"], mod_I["deletion_matrices"],
--> 506 mod_I["ori_sequence"], inverse=trim_inverse))
507
508 mod_I["homooligomers"] = [mod_I["homooligomers"][c] for c in mod_I["chains"]]

/content/colabfold_alphafold.py in trim_inputs(trim, msas, deletion_matrices, ori_seq, inverse)
407 trim_idx_i = trim_idx_j = global_idx
408 if i != "" and i[0] in ascii_uppercase:
--> 409 trim_idx_i,i = chain_idx[i[0]], i[1:]
410 if j != "" and j[0] in ascii_uppercase:
411 trim_idx_j,j = chain_idx[j[0]], j[1:]

KeyError: 'T'
“

Steps to Reproduce (for bugs)

Please make sure to reproduce the issue after a "Factory Reset" in Colab.
If running locally ypdate you local installation colabfold_batch to the newest version.
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ColabFold Output (for bugs)

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Context

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Your Environment

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Start with AlphaFold2_advanced.ipynb and the prep_filter and trim_inputs entry points in colabfold_alphafold.py, especially the chain parsing around line 409. Reproduce the reported trim_inverse input and inspect how chain identifiers are resolved. Done means the specified antigen epitope trim completes without the reported KeyError and produces results.