Normally an SMTP server will return an error, and smtplib will then issue an
RSET to return the connection to the known starting state.  Some servers,
however, disconnect after issuing certain errors.  When we issue the RSET,
this would result in raising an SMTPServerDisconnected error, *instead* of
returning the error code the user of the library was expecting.  This fix
makes the internal RSET calls ignore the disconnection so that the error code
is returned.  The user of the library will then get the SMTPServerDisconnected
error the next time they try to talk to the server.

Patch by Kushal Das.

Fixes issue20307.  No Misc/NEWS entry because frankly this is an
esoteric platform for anyone to be figuring out how to cross compile
CPython for.

Patch by Sam Lucidi.

Issue #7776: Fix ``Host:'' header and reconnection when using http.client.HTTPConnection.set_tunnel().

Patch by Nikolaus Rath.

Issue #20624: Exception docs wording tweak - clarify that it's okay to inherit from a subclass of Exception.

Debugged by Victor.

Bug reported by Guido Vranken.

If the input stream encoding couldn't encode one or more of the
non-ascii characters in the prompt, it would fail, throwing a
UnicodeEncodeError.  Now if that happens we re-encoding using the
'replace' error handler.

Patch by Kushal Das.

Patch by Berker Peksag.

section of the FAQ.

Patch by Kushal Das.