drop python3.9

Author: Zeitsperre

environment-dev.yml

@@ -3,7 +3,7 @@ channels:
   - conda-forge
   - nodefaults
 dependencies:
-  - python>=3.9,<3.14
+  - python>=3.10,<3.14
   # Requirements
   - cftime
   - dask

pyproject.toml

@@ -15,7 +15,7 @@ maintainers = [
 ]
 description = "Tools for manipulating and opening NCML (NetCDF Markup) files with/for xarray"
 readme = {file = "README.rst", content-type = "text/x-rst"}
-requires-python = ">=3.9.0"
+requires-python = ">=3.10.0"
 keywords = ["xncml", "xarray", "netcdf", "ncml"]
 license = {file = "LICENSE"}
 classifiers = [
@@ -26,7 +26,6 @@ classifiers = [
   "Natural Language :: English",
   "Operating System :: OS Independent",
   "Programming Language :: Python :: 3",
-  "Programming Language :: Python :: 3.9",
   "Programming Language :: Python :: 3.10",
   "Programming Language :: Python :: 3.11",
   "Programming Language :: Python :: 3.12",
@@ -199,7 +198,7 @@ exclude = [
 
 [tool.mypy]
 files = "."
-python_version = 3.9
+python_version = 3.10
 show_error_codes = true
 strict = true
 warn_no_return = true