get rid of index

[tiemvanderdeure]

index is removed in DD 0.30, so we might as well get rid of it already.

Makes it much easier to test the breaking branch of DD without running into these silly errors (you're welcome).

[codecov]

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 83.33%. Comparing base (f1c4b75) to head (fac42a7).
⚠️ Report is 42 commits behind head on main.

Additional details and impacted files

@@            Coverage Diff             @@
##             main    #1029      +/-   ##
==========================================
+ Coverage   82.89%   83.33%   +0.43%     
==========================================
  Files          58       58              
  Lines        5425     5333      -92     
==========================================
- Hits         4497     4444      -53     
+ Misses        928      889      -39     

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[rafaqz]

Really need to switch to parent(lookup(d)) not lookup(d) esp with plotting.

Lets avoid any complications and responsibities by returning types we dont own .