Initial pass of removing Python 2 support

This commit removes Six as a dependency for Pelican, replacing the
relevant aliases with the proper Python 3 imports. It also removes
references to Python 2 logic that did not require Six.

pelican/log.py

@@ -1,17 +1,9 @@
 # -*- coding: utf-8 -*-
-from __future__ import print_function, unicode_literals
 
-import locale
 import logging
 import os
 import sys
 from collections import defaultdict
-try:
-    from collections.abc import Mapping
-except ImportError:
-    from collections import Mapping
-
-import six
 
 __all__ = [
     'init'
@@ -29,20 +21,17 @@ class BaseFormatter(logging.Formatter):
         # format multiline messages 'nicely' to make it clear they are together
         record.msg = record.msg.replace('\n', '\n  | ')
         record.args = tuple(arg.replace('\n', '\n  | ') if
-                            isinstance(arg, six.string_types) else
+                            isinstance(arg, str) else
                             arg for arg in record.args)
         return super(BaseFormatter, self).format(record)
 
     def formatException(self, ei):
         ''' prefix traceback info for better representation '''
-        # .formatException returns a bytestring in py2 and unicode in py3
-        # since .format will handle unicode conversion,
-        # str() calls are used to normalize formatting string
         s = super(BaseFormatter, self).formatException(ei)
         # fancy format traceback
-        s = str('\n').join(str('  | ') + line for line in s.splitlines())
+        s = '\n'.join('  | ' + line for line in s.splitlines())
         # separate the traceback from the preceding lines
-        s = str('  |___\n{}').format(s)
+        s = '  |___\n{}'.format(s)
         return s
 
     def _get_levelname(self, name):
@@ -140,41 +129,7 @@ class LimitFilter(logging.Filter):
         return True
 
 
-class SafeLogger(logging.Logger):
-    """
-    Base Logger which properly encodes Exceptions in Py2
-    """
-    _exc_encoding = locale.getpreferredencoding()
-
-    def _log(self, level, msg, args, exc_info=None, extra=None):
-        # if the only argument is a Mapping, Logger uses that for formatting
-        # format values for that case
-        if args and len(args) == 1 and isinstance(args[0], Mapping):
-            args = ({k: self._decode_arg(v) for k, v in args[0].items()},)
-        # otherwise, format each arg
-        else:
-            args = tuple(self._decode_arg(arg) for arg in args)
-        super(SafeLogger, self)._log(
-            level, msg, args, exc_info=exc_info, extra=extra)
-
-    def _decode_arg(self, arg):
-        '''
-        properly decode an arg for Py2 if it's Exception
-
-
-        localized systems have errors in native language if locale is set
-        so convert the message to unicode with the correct encoding
-        '''
-        if isinstance(arg, Exception):
-            text = str('%s: %s') % (arg.__class__.__name__, arg)
-            if six.PY2:
-                text = text.decode(self._exc_encoding)
-            return text
-        else:
-            return arg
-
-
-class LimitLogger(SafeLogger):
+class LimitLogger(logging.Logger):
     """
     A logger which adds LimitFilter automatically
     """