In the preferences tab, you can enable a pre import script. This script, will be called before every import and it would be possible for the user to do additional action, before the asset is imported into Houdini.

Untitled

The about to be imported assets filename, is available with the following variable: hou.session.ODAssetLibFile

Sample Script (saved as prescript.py) It simply prints the file thats about to be imported.

print ("We are about to import file:", hou.session.ODAssetLibFile)