Remove support for Python 3.7 (#747)

.github/workflows/pytest-legacy.yml

@@ -20,7 +20,7 @@ jobs:
     - name: Set up Python
       uses: actions/setup-python@v4
       with:
-        python-version: '3.7.13'
+        python-version: '3.8'
 
     - name: Install specific out-dated version of dependencies
       # Update the package requirements when changing minimum dependency versions

.github/workflows/pytest.yml

@@ -22,8 +22,6 @@ jobs:
         - '3.10'
         - '3.9'
         - '3.8'
-        # Remove dependency `importlib_metadata` when dropping support for Python 3.7
-        - '3.7'
 
       fail-fast: false
 

README.md

@@ -8,7 +8,7 @@ pyam: analysis & visualization <br /> of integrated-assessment and macro-energy
 
 <!-- replace python version by dynamic reference to pypi once Python versions are configured there -->
 [![Code style: black](https://img.shields.io/badge/code%20style-black-000000.svg)](https://github.com/psf/black)
-[![python](https://img.shields.io/badge/python-≥3.7,<3.12-blue?logo=python&logoColor=white)](https://github.com/IAMconsortium/pyam)
+[![python](https://img.shields.io/badge/python-≥3.8,<3.12-blue?logo=python&logoColor=white)](https://github.com/IAMconsortium/pyam)
 [![pytest](https://github.com/IAMconsortium/pyam/actions/workflows/pytest.yml/badge.svg)](https://github.com/IAMconsortium/pyam/actions/workflows/pytest.yml)
 [![ReadTheDocs](https://readthedocs.org/projects/pyam-iamc/badge/?version=latest)](https://pyam-iamc.readthedocs.io/en/latest/?badge=latest)
 [![codecov](https://codecov.io/gh/IAMconsortium/pyam/branch/main/graph/badge.svg)](https://codecov.io/gh/IAMconsortium/pyam)

RELEASE_NOTES.md

@@ -1,5 +1,7 @@
 # Next Release
 
+- [#747](https://github.com/IAMconsortium/pyam/pull/747) Drop support for Python 3.7 #747
+
 # Release v1.9.0
 
 ## Highlights

docs/index.rst

@@ -24,7 +24,7 @@ Release v\ |version|.
 .. |black| image:: https://img.shields.io/badge/code%20style-black-000000.svg
    :target: https://github.com/psf/black
 
-.. |python| image:: https://img.shields.io/badge/python-≥3.7,<3.12-blue?logo=python&logoColor=white
+.. |python| image:: https://img.shields.io/badge/python-≥3.8,<3.12-blue?logo=python&logoColor=white
    :target: https://github.com/IAMconsortium/pyam
 
 .. |pytest| image:: https://github.com/IAMconsortium/pyam/actions/workflows/pytest.yml/badge.svg

pyam/__init__.py

@@ -1,14 +1,8 @@
+from importlib.metadata import version, PackageNotFoundError
 import logging
 from pathlib import Path
 from setuptools_scm import get_version
 
-# use standard library for Python >=3.8
-try:
-    from importlib.metadata import version, PackageNotFoundError
-# use dedicated package for Python 3.7
-except ModuleNotFoundError:
-    from importlib_metadata import version, PackageNotFoundError
-
 from pyam.core import *
 from pyam.slice import IamSlice  # noqa: F401
 from pyam.utils import *

setup.cfg

@@ -19,7 +19,7 @@ classifiers =
 [options]
 packages = pyam
 include_package_data = True
-python_requires = >=3.7.1, <3.12
+python_requires = >=3.8, <3.12
 
 # NOTE TO DEVS
 # If you change a minimum version below, please explicitly implement the change
@@ -32,6 +32,7 @@ install_requires =
     pyjwt
     httpx[http2]
     openpyxl
+    # remove exception in test_io.py when changing requirement to pandas ≥ 1.5
     pandas >= 1.2.0
     scipy
     pint >= 0.13
@@ -42,8 +43,6 @@ install_requires =
     setuptools >= 41
     setuptools_scm
     wquantiles
-    # required explicitly for Python 3.7
-    importlib_metadata
     xlsxwriter
 setup_requires =
     setuptools >= 41

tests/test_io.py

@@ -68,7 +68,7 @@ def test_io_csv_none(test_df_year):
     )
     try:
         assert test_df_year.to_csv(lineterminator="\n") == exp
-    # special treatment for Python 3.7 and pandas < 1.5
+    # special treatment for pandas < 1.5 (used in the legacy tests)
     except TypeError:
         assert test_df_year.to_csv(line_terminator="\n") == exp