From a2e5d5501409067a0420ac51a09c725b1e0659d1 Mon Sep 17 00:00:00 2001
From: Paul Natsuo Kishimoto <mail@paul.kishimoto.name>
Date: Tue, 19 Sep 2023 14:51:19 +0200
Subject: [PATCH] Drop support for Python 3.7

---
 .github/workflows/pytest.yaml | 3 +--
 RELEASE_NOTES.rst             | 1 +
 doc/install.rst               | 5 +++++
 ixmp/__init__.py              | 6 +-----
 pyproject.toml                | 6 ++----
 5 files changed, 10 insertions(+), 11 deletions(-)

diff --git a/.github/workflows/pytest.yaml b/.github/workflows/pytest.yaml
index cf0d92140..7615758eb 100644
--- a/.github/workflows/pytest.yaml
+++ b/.github/workflows/pytest.yaml
@@ -26,8 +26,7 @@ jobs:
         - ubuntu-latest
         - windows-latest
         python-version:
-        - "3.7"  # Earliest version supported by ixmp
-        - "3.8"
+        - "3.8"  # Earliest version supported by ixmp
         - "3.9"
         - "3.10"
         - "3.11"  # Latest supported by ixmp
diff --git a/RELEASE_NOTES.rst b/RELEASE_NOTES.rst
index b7573fa42..aafecacbf 100644
--- a/RELEASE_NOTES.rst
+++ b/RELEASE_NOTES.rst
@@ -4,6 +4,7 @@ Next release
 .. All changes
 .. -----------
 
+- Support for Python 3.7 is dropped (:pull:`492`).
 - New :func:`.utils.discard_on_error` and matching argument to :meth:`.TimeSeries.transact` to avoid locking :class:`.TimeSeries` / :class:`.Scenario` on failed operations with :class:`.JDBCBackend` (:pull:`488`).
 
 .. _v3.7.0:
diff --git a/doc/install.rst b/doc/install.rst
index 1eeab697e..d7d0d7251 100644
--- a/doc/install.rst
+++ b/doc/install.rst
@@ -31,6 +31,11 @@ Use cases for installing ixmp directly include:
 Install system dependencies
 ===========================
 
+Python
+------
+
+Python version 3.8 or later is required.
+
 GAMS (required)
 ---------------
 
diff --git a/ixmp/__init__.py b/ixmp/__init__.py
index 9284fa64a..1c745a663 100644
--- a/ixmp/__init__.py
+++ b/ixmp/__init__.py
@@ -1,9 +1,5 @@
 import logging
-
-try:
-    from importlib.metadata import PackageNotFoundError, version
-except ImportError:  # Python 3.7
-    from importlib_metadata import PackageNotFoundError, version  # type: ignore
+from importlib.metadata import PackageNotFoundError, version
 
 from ixmp._config import config
 from ixmp.backend import BACKENDS, IAMC_IDX, ItemType
diff --git a/pyproject.toml b/pyproject.toml
index 1a75a90a6..7b6bc5fc0 100644
--- a/pyproject.toml
+++ b/pyproject.toml
@@ -20,7 +20,6 @@ classifiers = [
   "Operating System :: OS Independent",
   "Programming Language :: Python",
   "Programming Language :: Python :: 3",
-  "Programming Language :: Python :: 3.7",
   "Programming Language :: Python :: 3.8",
   "Programming Language :: Python :: 3.9",
   "Programming Language :: Python :: 3.10",
@@ -29,11 +28,10 @@ classifiers = [
   "Topic :: Scientific/Engineering",
   "Topic :: Scientific/Engineering :: Information Analysis",
 ]
+requires-python = ">=3.8"
 dependencies = [
   "click",
-  "genno <= 1.13; python_version < '3.8'",
-  "genno >= 1.16; python_version >= '3.8'",
-  "importlib_metadata; python_version < '3.8'",
+  "genno >= 1.16",
   "JPype1 >= 1.2.1",
   "openpyxl",
   "pandas >= 1.2",