only lacks the instrument_used data and units of measurement
NOTE: units of measurement are hard to collect, but could be assumed
considering our instruments are standard
takes API key and elabid of the "entrypoint" sample as input
returns indented JSON with the reconstructed dataset!
currently lacks instruments_used data (matter of minutes)
and all the layer data (already present in Layer-class objects)
the fix changes "sample_data" - which was residual from copy-pasting the
call_entrypoint... function and therefore undefined - with
"material_data" which is very well defined in the previous line
