Remove Python 2.x compatibility

.travis.yml

@@ -20,39 +20,11 @@ matrix:
   - python: "nightly"
   # - python: "pypy3"
 
-  - name: Python 2.7 + latest Sphinx
-    python: "2.7"
-    install: &py2-install
-      - python2 --version
-      - python2 -m pip install .
-      - python2 -m pip install sphinxcontrib-bibtex==0.4.2
-      - python2 -m pip install sphinxcontrib-svg2pdfconverter
-      - python2 -m pip install ipywidgets
-      - python2 -m pip install 'sphinx-copybutton<0.2.6'
-    script: &py2-script
-      - python2 -m nbsphinx
-      # We don't execute, because the example notebooks use Python 3
-      - python2 -m sphinx doc/ doc/_build/ -W -b html -D nbsphinx_execute=never
-
   - name: default Python + latest Sphinx
     os: osx
     language: generic
     python: ""
 
-  - name: Python 2.7 + latest Sphinx
-    os: osx
-    language: generic
-    python: ""
-    addons:
-      homebrew:
-        update: true
-        packages:
-          - python@2
-          - pandoc
-          - librsvg
-    install: *py2-install
-    script: *py2-script
-
   allow_failures:
     - python: "nightly"
 

setup.cfg

@@ -1,5 +1,2 @@
-[bdist_wheel]
-universal=1
-
 [metadata]
 license_file = LICENSE

setup.py

@@ -12,7 +12,7 @@
     version=__version__,
     package_dir={'': 'src'},
     py_modules=['nbsphinx'],
-    python_requires='>=2.7',
+    python_requires='>=3',
     install_requires=[
         'docutils',
         'jinja2',

src/nbsphinx.py

@@ -26,16 +26,12 @@
 __version__ = '0.5.1'
 
 import copy
+from html.parser import HTMLParser
 import json
 import os
 import re
 import subprocess
-try:
-    from urllib.parse import unquote  # Python 3.x
-    from html.parser import HTMLParser
-except ImportError:
-    from urllib2 import unquote  # Python 2.x
-    from HTMLParser import HTMLParser
+from urllib.parse import unquote
 
 import docutils
 from docutils.parsers import rst