python3: Remove six.PY2/six.PY3 checks.

tools/coveragerc

@@ -9,9 +9,6 @@ exclude_lines =
     raise NotImplementedError()
     # Don't require coverage for test suite AssertionError -- they're usually for clarity
     raise AssertionError
-    # Don't require coverage for Python 2/3 variations; it's impossible to cover on both
-    if six.PY3:
-    if six.PY2:
     # Don't require coverage for __unicode__ statements just used for printing
     def __unicode__[(]self[)]:
 

zerver/lib/bugdown/__init__.py

@@ -12,6 +12,7 @@ from six.moves import urllib
 import re
 import os.path
 import glob
+import html
 import twitter
 import platform
 import time
@@ -45,9 +46,6 @@ from zerver.lib.tex import render_tex
 import six
 from six.moves import range, html_parser
 
-if six.PY3:
-    import html
-
 # Format version of the bugdown rendering; stored along with rendered
 # messages so that we can efficiently determine what needs to be re-rendered
 version = 1
@@ -89,13 +87,6 @@ def image_preview_enabled_for_realm():
         return True
     return realm.inline_image_preview
 
-def unescape(s):
-    # type: (Text) -> (Text)
-    if six.PY2:
-        return html_parser.HTMLParser().unescape(s)
-    else:  # nocoverage since coverage.py doesn't understand else statements.
-        return html.unescape(s)
-
 def list_of_tlds():
     # type: () -> List[Text]
     # HACK we manually blacklist a few domains
@@ -584,7 +575,7 @@ class InlineInterestingLinkProcessor(markdown.treeprocessors.Treeprocessor):
             image_url = user.get('profile_image_url_https', user['profile_image_url'])
             profile_img.set('src', image_url)
 
-            text = unescape(res['text'])
+            text = html.unescape(res['text'])
             urls = res.get('urls', [])
             user_mentions = res.get('user_mentions', [])
             media = res.get('media', [])  # type: List[Dict[Text, Any]]