ID 215774 - B-spline ShapeControlPoint no longer accessible via python

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Problem summary
B-spline ShapeControlPoint no longer accessible via python​ in 10.0v1 
 
It worked in 9.0v8

Customer reported version
nuke.10.0v1

Customer reported platform
OSX & Linux

Steps to reproduce

1. Open Nuke10.0v1​
2. Create a checkerboard node
3. Create a RotoPaint node 
4. Right click the Bezier tool (3rd icon down) and select B-spline 
5. Draw shape in the viewer
6. Select Rotopaint node
7. Copy and paste the following into the script editor and run it:

import nuke, nuke.rotopaint as rp 
rotoNode = nuke.selectedNode() 
rotoCurve = rotoNode['curves'] 
rotoRoot = rotoCurve.rootLayer 
for shape in rotoRoot: 
    for point in shape: ###this is where the error happens 
        print point

Reproduced by support
yes.  Nuke9.0v8 works, 10.0v1 fails, on OS 10.10.5

Expected behaviour
The expected result is something like this - which works in Nuke9.0v8:

# Result: <_curveknob.ShapeControlPoint object at 0x176159bd0>
<_curveknob.ShapeControlPoint object at 0x176159918>
<_curveknob.ShapeControlPoint object at 0x176159bd0>
<_curveknob.ShapeControlPoint object at 0x176159918>
<_curveknob.ShapeControlPoint object at 0x176159bd0>
<_curveknob.ShapeControlPoint object at 0x176159918>
<_curveknob.ShapeControlPoint object at 0x176159bd0>
<_curveknob.ShapeControlPoint object at 0x176159918>​


Actual behaviour

# Result: Traceback (most recent call last):
  File "<string>", line 6, in <module>
ValueError: internal error - missing feather control point data for this shape​

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