x86 Gentoo Non-Debug with X 3.10:
https://buildbot.python.org/all/#/builders/698/builds/112

This buildbot worker has Internet connection issues, so my concern is only how test_smtpnet handles Internet issues.

The two tests which fail use "with socket_helper.transient_internet(self.testServer):", but it seems like this context manager doesn't catch SMTPServerDisconnected.

Maybe transient_internet() should be modified to catch smtplib.SMTPServerDisconnected (or even the generic smtplib.SMTPException)?

======================================================================
ERROR: test_connect_default_port (test.test_smtpnet.SmtpSSLTest)
----------------------------------------------------------------------
Traceback (most recent call last):
  File "/buildbot/buildarea/cpython/3.10.ware-gentoo-x86.nondebug/build/Lib/test/test_smtpnet.py", line 60, in test_connect_default_port
    server = smtplib.SMTP_SSL(self.testServer)
  File "/buildbot/buildarea/cpython/3.10.ware-gentoo-x86.nondebug/build/Lib/smtplib.py", line 1045, in __init__
    SMTP.__init__(self, host, port, local_hostname, timeout,
  File "/buildbot/buildarea/cpython/3.10.ware-gentoo-x86.nondebug/build/Lib/smtplib.py", line 255, in __init__
    (code, msg) = self.connect(host, port)
  File "/buildbot/buildarea/cpython/3.10.ware-gentoo-x86.nondebug/build/Lib/smtplib.py", line 343, in connect
    (code, msg) = self.getreply()
  File "/buildbot/buildarea/cpython/3.10.ware-gentoo-x86.nondebug/build/Lib/smtplib.py", line 400, in getreply
    raise SMTPServerDisconnected("Connection unexpectedly closed")
smtplib.SMTPServerDisconnected: Connection unexpectedly closed

======================================================================
ERROR: test_connect_using_sslcontext (test.test_smtpnet.SmtpSSLTest)
----------------------------------------------------------------------
Traceback (most recent call last):
  File "/buildbot/buildarea/cpython/3.10.ware-gentoo-x86.nondebug/build/Lib/test/test_smtpnet.py", line 70, in test_connect_using_sslcontext
    server = smtplib.SMTP_SSL(self.testServer, self.remotePort, context=context)
  File "/buildbot/buildarea/cpython/3.10.ware-gentoo-x86.nondebug/build/Lib/smtplib.py", line 1045, in __init__
    SMTP.__init__(self, host, port, local_hostname, timeout,
  File "/buildbot/buildarea/cpython/3.10.ware-gentoo-x86.nondebug/build/Lib/smtplib.py", line 255, in __init__
    (code, msg) = self.connect(host, port)
  File "/buildbot/buildarea/cpython/3.10.ware-gentoo-x86.nondebug/build/Lib/smtplib.py", line 343, in connect
    (code, msg) = self.getreply()
  File "/buildbot/buildarea/cpython/3.10.ware-gentoo-x86.nondebug/build/Lib/smtplib.py", line 400, in getreply
    raise SMTPServerDisconnected("Connection unexpectedly closed")
smtplib.SMTPServerDisconnected: Connection unexpectedly closed