Please update the library to include support for upserting a batch of companies, as the current documentation inaccurately suggests this functionality is available.
Not available in the python library: Create or update a batch of companies by unique property values
Hey, @SItzkowitz 
Thanks for flagging this. Do have an example request and response along with the error you get that you can share? You can make a quick test from the documentation if that’s easier. I’ll include it when I reach out to my internal resources.
Thank you! — Jaycee