Github user zjffdu commented on the issue: https://github.com/apache/zeppelin/pull/3007 @lizhenhuan the protobuf in spark project is not related. The version you see in pom file is the protobu java version which is not the same as the python package version. I guess you hit this issue because that you install another version of protobuf before installing grpc. Could you try using virtualenv to create a clean enviroment ? You don't need to install protobuf expclitly, it will be installed automatically as the dependency of grpc.
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