What would be 'the best' hook function to use in the custom module installation to import entity data? This is supposed to be a one-time activity during the module installation only, after entity schema is built in the database and entities are initialized (to be able to use Entity API in the data import).
You do not want to use
hook_enable. If you used this, the database would be re-populated every time the module was re-enabled after being temporary disabled.