Upgrade to Python 3

[cclauss]

% flake8 . --count --select=E9,F63,F7,F82,Y --show-source --statistics

./blocktest.py:60:5: E999 SyntaxError: Missing parentheses in call to 'print'. Did you mean print(...)?
   print 'The item at index',ind,'is', ObjCInstance(obj)
    ^
./filter_subviews.py:22:2: E999 SyntaxError: Missing parentheses in call to 'print'. Did you mean print(...)?
print 'find'+'me'
 ^
./history_popup.py:55:17: F821 undefined name 'ListDataSourceList'
			self.items = ListDataSourceList([])
			             ^
./keycommands.py:18:3: E999 SyntaxError: Missing parentheses in call to 'print'. Did you mean print(...)?
	print 'hi'	
	 ^
./objc.py:164:13: F821 undefined name 'xrange'
   for i in xrange(num_methods.value):
            ^
./objc.py:310:39: F821 undefined name 'long'
         if not isinstance(key, (int, long)):
                                      ^
./objc.py:328:39: F821 undefined name 'long'
         if not isinstance(key, (int, long)):
                                      ^
./objc.py:345:39: F821 undefined name 'long'
         if not isinstance(key, (int, long)):
                                      ^
./objc.py:479:26: F821 undefined name 'unicode'
   if isinstance(py_obj, unicode):
                         ^
./objc.py:506:35: F821 undefined name 'basestring'
   if not isinstance(url_or_path, basestring):
                                  ^
./objcblock.py:34:8: E999 SyntaxError: Missing parentheses in call to 'print'. Did you mean print(...)?
      print self, idx  , obj
       ^
./objcnew.py:233:24: F821 undefined name 'basestring'
	if isinstance(result, basestring):
	                      ^
./objcnew.py:248:25: F821 undefined name 'basestring'
		if isinstance(member, basestring):
		                      ^
./objcnew.py:345:13: F821 undefined name 'xrange'
			for i in xrange(num_methods.value):
			         ^
./objcnew.py:444:33: F821 undefined name 'long'
			if not isinstance(key, (int, long)):
			                             ^
./objcnew.py:462:33: F821 undefined name 'long'
			if not isinstance(key, (int, long)):
			                             ^
./objcnew.py:479:33: F821 undefined name 'long'
			if not isinstance(key, (int, long)):
			                             ^
./objcnew.py:506:13: F821 undefined name 'xrange'
			for i in xrange(num_methods.value):
			         ^
./objcnew.py:535:43: F821 undefined name 'basestring'
	elif typecode == ':' and isinstance(arg, basestring):
	                                         ^
./objcnew.py:721:24: F821 undefined name 'unicode'
	if isinstance(py_obj, unicode):
	                      ^
./objcnew.py:748:33: F821 undefined name 'basestring'
	if not isinstance(url_or_path, basestring):
	                               ^
./objcnew.py:837:123: F821 undefined name 'xrange'
			type_encoding = 'v%i@0:8%s' % (sizeof(c_void_p) * (num_args + 2), ''.join('@%i' % ((i+2) * sizeof(c_void_p),) for i in xrange(num_args)))
			                                                                                                                       ^
4     E999 SyntaxError: Missing parentheses in call to 'print'. Did you mean print(...)?
18    F821 undefined name 'ListDataSourceList'
22