Require Python version 3.9 or higher (#24)

Author: paulromano

CHANGELOG.md

@@ -5,6 +5,12 @@ All notable changes to this project will be documented in this file.
 The format is based on [Keep a Changelog](http://keepachangelog.com/en/1.1.0/)
 and this project adheres to [Semantic Versioning](http://semver.org/spec/v2.0.0.html).
 
+## [0.1.6]
+
+### Fixed
+
+* Require Python version 3.9 or higher ([#24](https://github.com/paulromano/endf-python/pull/24))
+
 ## [0.1.5]
 
 ### Added

pyproject.toml

@@ -28,7 +28,7 @@ classifiers = [
     "Programming Language :: Python :: 3.12",
     "Programming Language :: Python :: 3.13",
 ]
-requires-python = ">=3.8"
+requires-python = ">=3.9"
 dependencies = [
     "numpy",
     "uncertainties",