[Bug]: No module named 'google.protobuf'

[dilumb]

What happened?

I'm trying to reproduce the example at https://a2a-protocol.org/latest/tutorials/python/5-start-server/ within my own code and getting the following error:

ModuleNotFoundError: No module named 'google.protobuf'

versions:
a2a-sdk 0.3.10
python 3.13

I can see .venv/lib/python3.13/site-packages/google/protobuf folder exists
As discussed in #326, I also attempted to install uv add "a2a-sdk[grpc]". I even tried uv add "a2a-sdk[all]" and manually installed protobuf. None of these work.

By the way following works

python -c "from google.protobuf.json_format import MessageToDict, MessageToJson, Parse; print('Protobuf is installed')"                       

printing "Protobuf is installed"

What could be going wrong?

Relevant log output

Traceback (most recent call last):
  File "<frozen runpy>", line 198, in _run_module_as_main
  File "<frozen runpy>", line 88, in _run_code
  File "/Users/user123/Documents/dev/llm/agents/test123/src/test123/agents/__main__.py", line 8, in <module>
    from a2a.server.apps import A2AStarletteApplication
  File "/Users/user123/Documents/dev/llm/agents/test123/.venv/lib/python3.13/site-packages/a2a/server/apps/__init__.py", line 3, in <module>
    from a2a.server.apps.jsonrpc import (
    ...<4 lines>...
    )
  File "/Users/user123/Documents/dev/llm/agents/test123/.venv/lib/python3.13/site-packages/a2a/server/apps/jsonrpc/__init__.py", line 3, in <module>
    from a2a.server.apps.jsonrpc.fastapi_app import A2AFastAPIApplication
  File "/Users/user123/Documents/dev/llm/agents/test123/.venv/lib/python3.13/site-packages/a2a/server/apps/jsonrpc/fastapi_app.py", line 21, in <module>
    from a2a.server.apps.jsonrpc.jsonrpc_app import (
    ...<2 lines>...
    )
  File "/Users/user123/Documents/dev/llm/agents/test123/.venv/lib/python3.13/site-packages/a2a/server/apps/jsonrpc/jsonrpc_app.py", line 19, in <module>
    from a2a.server.request_handlers.jsonrpc_handler import JSONRPCHandler
  File "/Users/user123/Documents/dev/llm/agents/test123/.venv/lib/python3.13/site-packages/a2a/server/request_handlers/__init__.py", line 14, in <module>
    from a2a.server.request_handlers.rest_handler import RESTHandler
  File "/Users/user123/Documents/dev/llm/agents/test123/.venv/lib/python3.13/site-packages/a2a/server/request_handlers/rest_handler.py", line 6, in <module>
    from google.protobuf.json_format import MessageToDict, MessageToJson, Parse
ModuleNotFoundError: No module named 'google.protobuf'

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[dilumb]

After more testing, I realized the issue applies to other transitive dependencies, not just a2a.
So, I removed the .venv folder and reran with uv run, which installed dependencies again.
The above problem no longer exists. So, I'm closing the issue