This was tested with PLA and PETG. PETG is much better choice due to better flexibility.
print instructions : material: PETGinfill: 100% is best , but works good with 70%+layout: horizontal
https://cad.onshape.com/documents/41674bd823d526feb6809857/w/7f9cd1b83fc90043c264fa62/e/65d4f56ffdc71b26fc03c30c
The author hasn't provided the model origin yet.