PDB mirror path not set

Hi
I am getting this error when trying mpnn sequence design.
Environment variable PDB_MIRROR_PATH not set. Will not be able to use function requiring this variable.

Is this something to worry about? I am using following script as suggested in #121 to run mpnn -

PDB_DIR_PATH="./renamed/"

cif_files=($PDB_DIR_PATH/*.cif)

for file in "${cif_files[@]}"; do
    mpnn --model_type "protein_mpnn" \
    --structure_path "$file" \
    --out_directory MPNN \
    --batch_size 2 \
    --number_of_batches 1 \
    --omit '["CYS"]' \
    --is_legacy_weights "True" \
    --checkpoint_path "/opt/checkpoints/solublempnn_v_48_020.pt"
done

Start by locating the code that checks PDB_MIRROR_PATH and trace whether the shown mpnn command requires it for structure_path inputs. Confirm the expected behavior for this script and document or reproduce the required configuration so the warning's impact is clear.