ID 308781 - Reading Alembic / .abc files into Nuke Pythonically doesn't populate knobs

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Problem summary
Reading Alembic / .abc files into Nuke Pythonically doesn't populate knobs unless the user interacts with the GUI or Renders a frame

Customer reported version
nuke.10.5v1

Customer reported platform
centos6

Steps to reproduce

1) Open Nuke

2) Download the attached .abc file

3) Run the below script, changing the first path to the path of the .abc file:

geo = nuke.createNode('ReadGeo2', inpanel=False)
geo['file'].setValue('<path/to/alembic>/simplecube.abc')
render = nuke.createNode('ScanlineRender', inpanel=False)
cam = nuke.createNode('Camera2', inpanel=False)
cam['translate'].setValue([50, 20,18])
write = nuke.createNode('Write', inpanel=False)
write['file'].fromUserText('/null.null')
render.setInput(2, cam)
render.setInput(1, geo)
write.setInput(0, render)
print geo['scene_view'].getAllItems()

nuke.execute(write, 1, 1)
print geo['scene_view'].getAllItems()
The first print geo will return ---------, after rendering the comp, the second print geo will print the mesh correctly

Workaround
Rendering the the ReadGeo node causes the knobs to be loaded correctly

Reproduced by support
This problem has been reproduced in:
Nuke 11.2v3 - Windows 7 - Mac OSX 10.12 - CentOS 6.9
Nuke 11.1v6 - Windows 7 - Mac OSX 10.12 - CentOS 6.9
Nuke 11.1v6 - Windows 7 - Mac OSX 10.12 - CentOS 6.9
Nuke 11.0v4 - Windows 7 - Mac OSX 10.12 - CentOS 6.9
Nuke 11.0v1 - Windows
Nuke 10.5v5 - Windows
Nuke 10.5v1 - Windows
Nuke 10.0v6 - Windows
Nuke 10.0v1 - Windows
Nuke 9.0v9 - Windows
Nuke 9.0v1 - Windows
Nuke 8.0v7 - Windows
Nuke 8.0v1 - Windows
Nuke 7.0v10 - Windows 

Earliest version tested
Nuke 7.0v10 as that was the earliest we regression check

Expected behaviour
For the ReadGeo knobs to be loaded correctly when adding an alembic file

Actual behaviour
The knobs were not loaded unless the Write node was rendered

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