patch 8.1.1984: more functions can be used as methods

Problem:    More functions can be used as methods.
Solution:   Make various functions usable as a method.
diff --git a/src/testdir/test_python2.vim b/src/testdir/test_python2.vim
index 61cf959..de5b0c9 100644
--- a/src/testdir/test_python2.vim
+++ b/src/testdir/test_python2.vim
@@ -54,7 +54,7 @@
 
   try
     py f = vim.Function('\x80\xfdR' + vim.eval('s:foo()'))
-    call assert_equal(name, pyeval('f.name'))
+    call assert_equal(name, 'f.name'->pyeval())
   catch
     call assert_false(v:exception)
   endtry