19 August 2019 -remove socket setblocking() calls which should be no longer needed, and which may have caused hangups. Thanks: Viacheslav Chimishuk. -correct version number string in error message. Thanks: Piet van Oostrum.
5.13
22 February 2019 -second attempt at fixing SNI change with Python < 2.7. Thanks: "Cimbal".
5.12
22 February 2019 -bugfix: the SNI change broke something else with Python 2.6 and earlier; fixed. Thanks: "Cimbal".
5.11
13 February 2019 -bugfix: the SNI change did not work correctly with Python < 2.7.13; should be fixed now. Thanks: Scott Robbins.
5.10
12 February 2019 -experimental: when SSL SNI support is present in the underlying Python (and OpenSSL), send SNI by default in the SSL setup. This should work around Gmail's brokenness with TLSv.1.3 connections when SNI is not sent.
5.9
-documentation-only update; add note with workaround for Gmail SSL connections with OpenSSL 1.1.1 and later. -update copyright dates.