[issue20647] 3.4 cherry-pick: d50a95fab002 add tracemalloc.Traceback.format() method

[R. David Murray]

R. David Murray added the comment:

Drat.  Typoed the message number, this commit is for #20674.

----------
nosy: +r.david.murray

_______________________________________
Python tracker <report at bugs.python.org>
<http://bugs.python.org/issue20647>
_______________________________________