Issue #19849: selectors: Document the possibility of early select() wakeup upon
EINTR.
Issue #18994: Add a missing check for a return value in fcntmodule. Patch by
Vajrasky Kok.
Issue #11480: Fixed copy.copy to work with classes with custom metaclasses.

Patch by Daniel Urban.
Issue #11480: Merge with 3.3.
Fixes issue #15798: subprocess.Popen() no longer fails if file
descriptor 0, 1 or 2 is closed. (correct fix for 3.4 this time)
Issue #19754: Make pickletools.optimize respect the frame size target.
Issue #19754: Fix typo.
Fixes issue #15798: subprocess.Popen() no longer fails if file
descriptor 0, 1 or 2 is closed.
The errpipe_write fd will always be >= 3.
null merge (3.4 already has its own fix for this).
Issue #19509: Add SSLContext.check_hostname to match the peer's certificate
with server_hostname on handshake.
Issue #19781: ftplib now supports SSLContext.check_hostname and server name
indication for TLS/SSL connections.