Github user jongyoul commented on the issue:
https://github.com/apache/zeppelin/pull/2908
Oh. This is the same one with my PR #2910. I've checked it's not always a
string type. @zjffdu Could you please check my PR and merge both of them?
---
Github user zjffdu commented on the issue:
https://github.com/apache/zeppelin/pull/2908
```
I'm not 100% sure when map.get(key) is a StringMap?
```
This is due to the schema changes of interpeter.json, and we need to
support different schemas for backward compatibility.
