[MRG] FIX: allow reading experimental dipole

[jasmainak]

closes #420

[codecov-commenter]

Codecov Report

Merging #421 (54c1e63) into master (7c48e69) will increase coverage by 0.03%.
The diff coverage is 100.00%.

❗ Current head 54c1e63 differs from pull request most recent head 71fc1e6. Consider uploading reports for the commit 71fc1e6 to get more accurate results

@@            Coverage Diff             @@
##           master     #421      +/-   ##
==========================================
+ Coverage   88.40%   88.44%   +0.03%     
==========================================
  Files          18       18              
  Lines        3235     3246      +11     
==========================================
+ Hits         2860     2871      +11     
  Misses        375      375              

Impacted Files	Coverage Δ
hnn_core/dipole.py	91.44% <100.00%> (+0.66%)	⬆️

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[rythorpe]

Does anyone else want to take a look or shall we merge?

[rythorpe]

I'm going to go ahead and merge this to maintain forward momentum. Thanks @jasmainak!