How to construct ligand summary path URL?

[jdwestbrook]

I am trying to understand how you construct ligand summary page URLs
for the Pharos web site.

For instance, acetazolamide / CHEMBL20 has the URL:

https://pharos.nih.gov/ligands/9XY1117CMPQQ

The 9XY1117CMPQQ HASH does not appear in the SQL dump of
the Pharos database that I can find. If the string '9XY1117CMPQQ' is
derived from the LyChI hash, could you please describe precisely
which LyChI options produce this key, or what transformation of
the 4-layer LyChI hash produces this string.

Thanks very much for you help with this.