Issue #20387: Merge patch and test

diff --cc Misc/NEWS
index 02b129a508359d8535d2bd474837f9c6bf625de0,496a92e194d693bfae757557cb17c94b8a9787ab..f2539d1f8bd5eda04934b8077fd43f2249dde674
--- 1/Misc/NEWS
--- 2/Misc/NEWS
+++ b/Misc/NEWS
@@@ -60,11 -60,9 +60,14 @@@ Core and Builtin
  Library
  -------
  
+ - Issue #20387: Restore semantic round-trip correctness in tokenize/untokenize
+   for tab-indented blocks.
+ 
 +- Issue #24336: The contextmanager decorator now works with functions with
 +  keyword arguments called "func" and "self".  Patch by Martin Panter.
 +
 +- Issue #24489: ensure a previously set C errno doesn't disturb cmath.polar().
 +
  - Issue #5633: Fixed timeit when the statement is a string and the setup is not.
  
  - Issue #24326: Fixed audioop.ratecv() with non-default weightB argument.