How to avoid "TypeError: Couldn't build proto file into descriptor pool: duplicate symbol 'core.grpc_interface.Explosion'"

Language / runtime: Python 3.12.3

Operating system: Linux (Ubuntu 24.04)

Protoc / protobuf versions:

• protoc (libprotoc) 31.0
• protobuf 6.30.1
• grpcio-tools 1.73.1

Description:

• My project has two independent .proto files.
• Both files use the same package and repeat several message definitions, e.g.:

protobuf
// file: grpc_interface_1.proto
syntax = "proto3";
package core.grpc_interface;

message Message1 {
  string id = 1;
}

// file: grpc_interface_2.proto
syntax = "proto3";
package core.grpc_interface;

message Message1 {            // identical name
  string id = 1;
}

• Each file is compiled to Python with:

python -m grpc_tools.protoc \
  -I=. --python_out=. --grpc_python_out=.  grpc_interface_1.proto
python -m grpc_tools.protoc \
  -I=. --python_out=. --grpc_python_out=.  grpc_interface_2.proto

• During a single pytest session the test code imports both generated files:

import grpc_interface_1_pb2       # works
import grpc_interface_2_pb2       # boom

• and raises

TypeError: Couldn't build proto file into descriptor pool:
           duplicate symbol 'core.grpc_interface.Message1'

Question:

• How can I use two proto files that both define the same message?

Notes:

• I understand duplicate symbols are currently rejected by the global DescriptorPool, but I could not find an official statement in the documentation or release notes.

I tried using several command options, but none of them worked.