<!-- If you suspect this could be a bug, follow the template. --> ### What version of Dgraph are you using? 1.1.1 ### Have you tried reproducing the issue with the latest release? yes ### What is the hardware spec (RAM, OS)? 8 GB os 10.15.2 ### Steps to reproduce the issue (command/config used to run Dgraph). ran mutation `{ "set": [{ "uid": < 0x3 > , "inhabits": { "uid": "0x2711" } }, { "uid": < 0x4 > , "inhabits": { "uid": "0x2711" } } ] } ` ### Expected behaviour and actual result. tell me which line the error is on and what's causing the error