It checks that a SyntaxWarning is raised when compile specified
statement, that it is raised only once, that it is converted to
a SyntaxError when raised as exception, and that both warning and
exception objects have corresponding attributes.
Issue #28691: Fix warn_invalid_escape_sequence(): handle correctly
DeprecationWarning raised as an exception. First clear the current exception to
replace the DeprecationWarning exception with a SyntaxError exception.
Unit test written by Serhiy Storchaka.
Serhiy Storchaka
Anthony Sottile
Victor Stinner
Eric V. Smith
Zachary Ware