ID 387216 - mari.lights.list() returns an empty list

Problem summary
mari.lights.list() returns an empty list 

Customer reported version

4.5v1

Customer reported platform
windows10

Steps to reproduce

1) Open Mari and an example project

2) Open the Python Console 

3) Execute the following: mari.lights.list()

result: Mari returns an empty list 

Expected behaviour

Mari should return all of the lights in the scene

Actual behaviour
Mari returns an empty list 

Workaround
Unknown.

Reproduced by support
This bug has been reproduced in:

Mari 4.5v1 - Windows 10 - CentOS 7 - regression

Unable to reproduce bug in:

Mari 4.2v2 - Windows 10

Mari 4.1v1 - Windows 10 - CentOS 7

Earliest version tested
4.2v2 - This issue no longer appears in this version and has regressed