Cannot generate auto-import when undefined function is used as decorator

[ThiefMaster]

Environment data

• Language Server version: 0.5.50.0
• OS and version: Gentoo Linux
• Python version (& distribution if applicable, e.g. Anaconda): 3.8

Expected behavior

Being able to autogenerate the import for the decorator as well.

Actual behavior

The import can only be autogenerated for the normal function call.