Fix closes issue1067702  The problem with close multiple ftp transfers were due cases where sockets/file were not closed immediately. Tightned those cases and failure is no longer observed.

Patch by Akira Kitada.

The new wording is based on the comments in the code, which
match the actual behavior.

"#3067: locale.setlocale() accepts a Unicode locale."

processes if negative or null.

Patch by July Tikhonov.

This makes them work like the close provided by regular file objects.  This
patch also backports the close-the-underlying-file code for _ProxyFile objects
that was introduced along with context manager support in the 3.x branch.

connection if its getresponse() method fails with a socket error. Patch written
by Ezio Melotti.

This allows findsource() to work in doctests.

A patch from Dirkjan Ochtman.