Predictive Model Markup Language (PMML) was released in 1997 to solve a very similar problem (but for lots of predictive models). I don't know that it ever really caught on. That was also promoted by the tool builders but not by the users.
PMML is alive and well for sure. It really only covers simpler model types so something aimed at deep nets models is a welcome addition. However, PMML is still alive and well because plenty of ML will continue to be based on simpler model types and modelers don't want to be tied down on choice of modeling tech even for simple model types.
While checking the wikipedia page, I'm surprised to see that it is still being developed (with a 2016 release): https://en.wikipedia.org/wiki/Predictive_Model_Markup_Langua...
Please note that in 1997 it was NOT ridiculous to use XML for this.