drop support for Python 3.9 and ensure compatibility with Poetry 2.3

Author: radoering

.github/workflows/main.yaml

@@ -19,7 +19,7 @@ jobs:
     strategy:
       matrix:
         os: [Ubuntu, macOS, Windows]
-        python-version: ["3.9", "3.10", "3.11", "3.12", "3.13", "3.14"]
+        python-version: ["3.10", "3.11", "3.12", "3.13", "3.14"]
         include:
           - os: Ubuntu
             image: ubuntu-latest

poetry.lock

@@ -5,7 +5,7 @@ description = "Poetry plugin to export the dependencies to various formats"
 authors = [{ name = "Sébastien Eustace", email = "[email protected]" }]
 license = "MIT"
 readme = "README.md"
-requires-python = ">=3.9,<4.0"
+requires-python = ">=3.10,<4.0"
 dependencies = [
     "poetry>=2.1.0,<3.0.0",
     "poetry-core>=2.1.0,<3.0.0",
@@ -45,7 +45,6 @@ pytest-github-actions-annotate-failures = "^0.1.7"
 
 [tool.ruff]
 fix = true
-target-version = "py39"
 line-length = 88
 extend-exclude = [
     "docs/*",

pyproject.toml

@@ -1,6 +1,6 @@
 from __future__ import annotations
 
-from poetry.utils._compat import metadata
+from importlib import metadata
 
 
 __version__ = metadata.version("poetry-plugin-export")  # type: ignore[no-untyped-call]