Drop support of Python 3.9

Author: andreArtelt

DEVELOPERS.md

@@ -4,7 +4,7 @@
 
 Objects should be immutable whenever possible -- this allows us to avoid unintended side effects. Never trust the user's input -- check all passed arguments carefully.
 
-Code must work with all current Python versions from 3.9 to 3.13. Also, code must work on all major platforms: Windows, Linux, and Mac OSX.
+Code must work with all current Python versions from 3.10 to 3.14. Also, code must work on all major platforms: Windows, Linux, and Mac OSX.
 
 ## Code Style Guide
 

README.md

@@ -27,7 +27,7 @@ Unique features of EPANET-PLUS that make it superior to other Python interfaces
 
 ## Installation
 
-Note that EPANET-PLUS supports Python 3.9 - 3.14. 
+Note that EPANET-PLUS supports Python 3.10 - 3.14. 
 The Python package contains the the C library as a C extension and is
 already pre-build for all major platforms.
 

docs/installation.rst

@@ -22,7 +22,7 @@ require the latest version of `gcc`:
 Installation of the Python Package
 ++++++++++++++++++++++++++++++++++
 
-Note that EPANET-PLUS supports Python 3.9 - 3.14
+Note that EPANET-PLUS supports Python 3.10 - 3.14
 
 .. note::
 

noxfile.py

@@ -1,7 +1,7 @@
 import nox
 
 
-@nox.session(python=["3.9", "3.10", "3.11", "3.12", "3.13", "3.14"])
+@nox.session(python=["3.10", "3.11", "3.12", "3.13", "3.14"])
 def test(session):
     session.install(".")
     session.install("-rREQUIREMENTS-DEV.txt")

pyproject.toml

@@ -9,12 +9,11 @@ authors = [
     {name = "André Artelt", email = "aartelt@techfak.uni-bielefeld.de"}
 ]
 license = "MIT"
-requires-python = ">=3.9"
+requires-python = ">=3.10"
 classifiers = [
     "Development Status :: 4 - Beta",
     "Intended Audience :: Science/Research",
     "Programming Language :: Python :: 3",
-    "Programming Language :: Python :: 3.9",
     "Programming Language :: Python :: 3.10",
     "Programming Language :: Python :: 3.11",
     "Programming Language :: Python :: 3.12",