Update supported versions

.github/workflows/tests.yml

@@ -12,11 +12,11 @@ on:
 jobs:
   test:
     name: "Python ${{ matrix.python-version }} ${{ matrix.name-suffix }}"
-    runs-on: ubuntu-18.04
+    runs-on: ubuntu-20.04
 
     strategy:
       matrix:
-        python-version: ["2.7", "3.5", "3.6", "3.7", "3.8", "3.9"]
+        python-version: ["3.6", "3.7", "3.8", "3.9", "3.10-dev"]
 
     steps:
       - uses: actions/checkout@v2

appveyor.yml

@@ -1,16 +1,18 @@
 # AppVeyor.com is a Continuous Integration service to build and run tests under
 # Windows
 
+image: Visual Studio 2019
+
 environment:
   matrix:
-     - PYTHON: "C:\\Python27"
-     - PYTHON: "C:\\Python27-x64"
-     - PYTHON: "C:\\Python34"
-     - PYTHON: "C:\\Python34-x64"
-     - PYTHON: "C:\\Python35"
-     - PYTHON: "C:\\Python35-x64"
      - PYTHON: "C:\\Python36"
      - PYTHON: "C:\\Python36-x64"
+     - PYTHON: "C:\\Python37"
+     - PYTHON: "C:\\Python37-x64"
+     - PYTHON: "C:\\Python38"
+     - PYTHON: "C:\\Python38-x64"
+     - PYTHON: "C:\\Python39"
+     - PYTHON: "C:\\Python39-x64"
 
 install:
   - "SET PATH=%PYTHON%;%PYTHON%\\Scripts;%PATH%"

cycler.py

@@ -40,17 +40,11 @@
     {'color': 'b', 'linestyle': '-.'}
 """
 
-from __future__ import (absolute_import, division, print_function,
-                        unicode_literals)
 
 import copy
 from functools import reduce
 from itertools import product, cycle
 from operator import mul, add
-import sys
-
-if sys.version_info < (3,):
-    from itertools import izip as zip
 
 __version__ = '0.10.0'
 
@@ -107,7 +101,7 @@ def concat(left, right):
     return reduce(add, (_cycler(k, _l[k] + _r[k]) for k in left.keys))
 
 
-class Cycler(object):
+class Cycler:
     """
     Composable cycles.
 
@@ -231,7 +225,7 @@ def _from_iter(cls, label, itr):
         """
         ret = cls(None)
         ret._left = list({label: v} for v in itr)
-        ret._keys = set([label])
+        ret._keys = {label}
         return ret
 
     def __getitem__(self, key):
@@ -263,7 +257,7 @@ def __add__(self, other):
         """
         if len(self) != len(other):
             raise ValueError("Can only add equal length cycles, "
-                             "not {0} and {1}".format(len(self), len(other)))
+                             "not {} and {}".format(len(self), len(other)))
         return Cycler(self, other, zip)
 
     def __mul__(self, other):
@@ -347,7 +341,7 @@ def __repr__(self):
         if self._right is None:
             lab = self.keys.pop()
             itr = list(v[lab] for v in self)
-            return "cycler({lab!r}, {itr!r})".format(lab=lab, itr=itr)
+            return f"cycler({lab!r}, {itr!r})"
         else:
             op = op_map.get(self._op, '?')
             msg = "({left!r} {op} {right!r})"
@@ -358,11 +352,11 @@ def _repr_html_(self):
         output = "<table>"
         sorted_keys = sorted(self.keys, key=repr)
         for key in sorted_keys:
-            output += "<th>{key!r}</th>".format(key=key)
+            output += f"<th>{key!r}</th>"
         for d in iter(self):
             output += "<tr>"
             for k in sorted_keys:
-                output += "<td>{val!r}</td>".format(val=d[k])
+                output += f"<td>{d[k]!r}</td>"
             output += "</tr>"
         output += "</table>"
         return output

doc/source/conf.py

@@ -1,5 +1,4 @@
 #!/usr/bin/env python3
-# -*- coding: utf-8 -*-
 #
 # cycler documentation build configuration file, created by
 # sphinx-quickstart on Wed Jul  1 13:32:53 2015.
@@ -273,7 +272,7 @@
 # If true, do not generate a @detailmenu in the "Top" node's menu.
 # texinfo_no_detailmenu = False
 
-intersphinx_mapping = {'python': ('https://docs.python.org/3.4', None),
+intersphinx_mapping = {'python': ('https://docs.python.org/3', None),
                        'matplotlb': ('https://matplotlib.org', None)}
 
 # ################ numpydoc config ####################

setup.py

@@ -7,17 +7,18 @@
       py_modules=['cycler'],
       description='Composable style cycles',
       url='https://github.com/matplotlib/cycler',
-      platforms='Cross platform (Linux, Mac OSX, Windows)',
+      platforms='Cross platform (Linux, macOS, Windows)',
       license="BSD",
-      python_requires='>=2.7, !=3.0.*, !=3.1.*, !=3.2.*, !=3.3.*',
+      python_requires='>=3.6',
       classifiers=['License :: OSI Approved :: BSD License',
                    'Development Status :: 4 - Beta',
-                   'Programming Language :: Python :: 2',
-                   'Programming Language :: Python :: 2.7',
                    'Programming Language :: Python :: 3',
-                   'Programming Language :: Python :: 3.4',
-                   'Programming Language :: Python :: 3.5',
                    'Programming Language :: Python :: 3.6',
+                   'Programming Language :: Python :: 3.7',
+                   'Programming Language :: Python :: 3.8',
+                   'Programming Language :: Python :: 3.9',
+                   'Programming Language :: Python :: 3.10',
+                   'Programming Language :: Python :: 3 :: Only',
                    ],
       keywords='cycle kwargs',
       )

test_cycler.py

@@ -1,19 +1,11 @@
-from __future__ import (absolute_import, division, print_function)
-
 from collections import defaultdict
 from operator import add, iadd, mul, imul
 from itertools import product, cycle, chain
-import sys
 
 import pytest
 
 from cycler import cycler, Cycler, concat
 
-if sys.version_info < (3,):
-    from itertools import izip as zip
-    range = xrange  # noqa
-    str = unicode  # noqa
-
 
 def _cycler_helper(c, length, keys, values):
     assert len(c) == length