Dropping python 2.7 support

Author: wvangeit

.github/workflows/main.yml

@@ -16,7 +16,7 @@ jobs:
     runs-on: ubuntu-latest
     strategy:
       matrix:
-        python-version: [2.7, 3.6, 3.7, 3.8, 3.9]
+        python-version: [3.6, 3.7, 3.8, 3.9]
 
     steps:
     - uses: actions/checkout@v2

README.rst

@@ -103,6 +103,7 @@ We are providing support using a chat channel on `Gitter <https://gitter.im/Blue
 
 News
 ====
+- 2021/08/30: BluePyOpt dropped Python 2.7 support.
 - 2017/01/04: BluePyOpt is now considered compatible with Python 3.6+.
 - 2016/11/10: BluePyOpt now supports NEURON point processes. This means we can fit parameters of Adex/GIF/Izhikevich models, and also synapse models.
 - 2016/06/14: Started a wiki: https://github.com/BlueBrain/BluePyOpt/wiki

setup.py

@@ -73,8 +73,7 @@
         'Environment :: Console',
         'License :: OSI Approved :: GNU Lesser General Public '
         'License v3 (LGPLv3)',
-        'Programming Language :: Python :: 2.7',
-        'Programming Language :: Python :: 3.6',
+        'Programming Language :: Python :: 3 :: Only',
         'Operating System :: POSIX',
         'Topic :: Scientific/Engineering',
         'Topic :: Utilities'],

tox.ini

@@ -1,9 +1,8 @@
 [tox]
-envlist = py{27,3}-{unit,functional,style}
+envlist = py{3}-{unit,functional,style}
 
 [gh-actions]
 python =
-    2.7: py27
     3.6: py3
     3.7: py3
     3.8: py3