os.unsetenv(key) Unset (delete) the environment variable named key. Such changes to the environment affect subprocesses started with os.system(), popen() or fork() and execv(). When unsetenv() is supported, deletion of items in os.environ is automatically translated into a corresponding call to unsetenv(); however, calls to unsetenv() don’t update os.environ, so it is actually preferable to delete items of os.environ. Availability: most flavors of Unix, Windows.

os.unlink(path, *, dir_fd=None) Remove (delete) the file path. This function is semantically identical to remove(); the unlink name is its traditional Unix name. Please see the documentation for remove() for further information. New in version 3.3: The dir_fd parameter.

os.uname() Returns information identifying the current operating system. The return value is an object with five attributes: sysname - operating system name nodename - name of machine on network (implementation-defined) release - operating system release version - operating system version machine - hardware identifier For backwards compatibility, this object is also iterable, behaving like a five-tuple containing sysname, nodename, release, version, and machine in that order. Some sys

os.umask(mask) Set the current numeric umask and return the previous umask.

os.ttyname(fd) Return a string which specifies the terminal device associated with file descriptor fd. If fd is not associated with a terminal device, an exception is raised. Availability: Unix.

os.truncate(path, length) Truncate the file corresponding to path, so that it is at most length bytes in size. This function can support specifying a file descriptor. Availability: Unix, Windows. New in version 3.3. Changed in version 3.5: Added support for Windows

os.times() Returns the current global process times. The return value is an object with five attributes: user - user time system - system time children_user - user time of all child processes children_system - system time of all child processes elapsed - elapsed real time since a fixed point in the past For backwards compatibility, this object also behaves like a five-tuple containing user, system, children_user, children_system, and elapsed in that order. See the Unix manual page tim

lines Height of the terminal window in characters.

columns Width of the terminal window in characters.

class os.terminal_size A subclass of tuple, holding (columns, lines) of the terminal window size. columns Width of the terminal window in characters. lines Height of the terminal window in characters.