Rule blocked: SENDIG-173

SEND rule 173: "If LBTOXGR or LBTOX are used; the sponsor is expected to provide the name of the scale and version used to map the terms, utilizing the Define-XML document **external codelist** attributes."

We do already have a function "define_variable_has_codelist" which checks on "ItemGroupDef.ItemDef.CodeListRef exists", which does not distinguish between normal define.xml codelists and "external codelists". The latter have the construct like:

<**ExternalCodeList** Dictionary="MedDRA" Version="22.0" href="https://www.meddra.org/"/>

i.e. have an "ExternalCodeList" child element of "CodeList" with at least the "Dictionary" and "Version" attributes.

Can a function named "define_variable_has_external_codelist" be developed?