Pypi package description

パッケージのメタデータは pyproject.toml にあります。まず [tool.poetry] セクションから始め、その readme 設定を README.md と比較します。PyPI の readme メタデータを設定し、ビルドされたパッケージの説明が設定されていることを確認します。

Currently the description for linfa on pypi is empty. Since you are using Poetry to fix this you just need to update the pyproject.toml file to include the long_description or in poetry it's just called readme.

At the top of the file it should look like this

[tool.poetry]
name = "linfa"
version = "0.1.0"
authors = ["LukeMathWalker <rust@lpalmieri.com>"]
description = "Python bindings for the Rust crate linfa, a Rust machine learning framework."
readme = "README.md"

You can actually use any txt or markdown file so it doesn't have to be the main readme file.
Also, there are some other settings it might be nice to include such as license, repository, hompage (if we have one) etc..
You can find a full list of possible settings here

I can go ahead and open a pull request with these changes but it might be quicker and easier for you to update them yourself since you know which settings are actually relevant