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Consider the following simple example:

Interpolation[{0, 1, 2, 3}]

Despite the FullForm of the output of this expression is

InterpolatingFunction[List[List[1,4]],List[5,3,0,List[4],List[4],0,0,0,0,Automatic,List[],List[],False],List[List[1,2,3,4]],List[List[0],List[1],List[2],List[3]],List[Automatic]]

what I actually see in the notebook is:

enter image description here

How can I emulate this behaviour for a user-defined Head?

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