I am trying to concatenate a group of fields, but there are some non-nullable entries that contain a single space.
This is an example of the setup I made in excel, and example results are in the "RESULT" field. The results I want but can't figure out are in the "DESIRED RESULT" field. Basically just to remove all the weird spaces put in by the non-nullable fields.

I am currently trying this code:
" ".join([str(i) for i in [ !STREET_NUM!, !PREDIR!, !PRETYPE!, !NAME!,!TYPE!, !SUFDIR!, !UNIT_TYPE!, !UNIT_NUM!] if i])
However, I think it is picking up the spaces as filled boxes within the program and spitting them out as double spaces in the final result. I can't figure out how to resolve this so it gives me the desired result.
It's also not an option to nullify those fields.
Any ideas? Thanks in advance.