Error NameError: name 'AsyncGenerator' is not defined

[jalo2312]

hi
I have a problem
when i run this line "uv run langflow run" appears this error:
NameError: name 'AsyncGenerator' is not defined
and i dont know how resolve

anyone can help me pls

[anntnzrb]

AsyncGenerator is imported inside TYPE_CHECKING block in src/lfx/src/lfx/cli/serve_app.py but used in runtime annotation at line 261. Move import outside TYPE_CHECKING block.

[jalo2312]

ok, but i dont have the code only i following the steps in the readme but i dont know why appears the error

[gokulhcl]

Downgrade fastapi and restart langflow

pip install "fastapi==0.119.1"

recent version of fastapi-0.123.9 is creating this issue.

Reference: https://github.com/fastapi/fastapi/releases/tag/0.123.7

[jalo2312]

thx, its work