test.support.bind_port(sock, host=HOST) Bind the socket to a free port and return the port number. Relies on ephemeral ports in order to ensure we are using an unbound port. This is important as many tests may be running simultaneously, especially in a buildbot environment. This method raises an exception if the sock.family is AF_INET and sock.type is SOCK_STREAM, and the socket has SO_REUSEADDR or SO_REUSEPORT set on it. Tests should never set these socket options for TCP/IP sockets. The on

@test.support.anticipate_failure(condition) A decorator to conditionally mark tests with unittest.expectedFailure(). Any use of this decorator should have an associated comment identifying the relevant tracker issue.

termios.tcsetattr(fd, when, attributes) Set the tty attributes for file descriptor fd from the attributes, which is a list like the one returned by tcgetattr(). The when argument determines when the attributes are changed: TCSANOW to change immediately, TCSADRAIN to change after transmitting all queued output, or TCSAFLUSH to change after transmitting all queued output and discarding all queued input.

termios.tcsendbreak(fd, duration) Send a break on file descriptor fd. A zero duration sends a break for 0.25 –0.5 seconds; a nonzero duration has a system dependent meaning.

termios.tcgetattr(fd) Return a list containing the tty attributes for file descriptor fd, as follows: [iflag, oflag, cflag, lflag, ispeed, ospeed, cc] where cc is a list of the tty special characters (each a string of length 1, except the items with indices VMIN and VTIME, which are integers when these fields are defined). The interpretation of the flags and the speeds as well as the indexing in the cc array must be done using the symbolic constants defined in the termios module.

termios.tcflush(fd, queue) Discard queued data on file descriptor fd. The queue selector specifies which queue: TCIFLUSH for the input queue, TCOFLUSH for the output queue, or TCIOFLUSH for both queues.

termios.tcflow(fd, action) Suspend or resume input or output on file descriptor fd. The action argument can be TCOOFF to suspend output, TCOON to restart output, TCIOFF to suspend input, or TCION to restart input.

termios.tcdrain(fd) Wait until all output written to file descriptor fd has been transmitted.

tempfile.TemporaryFile(mode='w+b', buffering=None, encoding=None, newline=None, suffix=None, prefix=None, dir=None) Return a file-like object that can be used as a temporary storage area. The file is created securely, using the same rules as mkstemp(). It will be destroyed as soon as it is closed (including an implicit close when the object is garbage collected). Under Unix, the directory entry for the file is either not created at all or is removed immediately after the file is created. Oth

tempfile.TemporaryDirectory(suffix=None, prefix=None, dir=None) This function securely creates a temporary directory using the same rules as mkdtemp(). The resulting object can be used as a context manager (see Examples). On completion of the context or destruction of the temporary directory object the newly created temporary directory and all its contents are removed from the filesystem. The directory name can be retrieved from the name attribute of the returned object. When the returned ob