How to use the billiard.process function in billiard

#
# Base type for contexts
#

class BaseContext(object):

    ProcessError = ProcessError
    BufferTooShort = BufferTooShort
    TimeoutError = TimeoutError
    AuthenticationError = AuthenticationError
    TimeLimitExceeded = TimeLimitExceeded
    SoftTimeLimitExceeded = SoftTimeLimitExceeded
    WorkerLostError = WorkerLostError

    current_process = staticmethod(process.current_process)
    active_children = staticmethod(process.active_children)

    if hasattr(os, 'cpu_count'):
        def cpu_count(self):
            '''Returns the number of CPUs in the system'''
            num = os.cpu_count()
            if num is None:
                raise NotImplementedError('cannot determine number of cpus')
            else:
                return num
    else:
        def cpu_count(self):  # noqa
            if sys.platform == 'win32':
                try:
                    num = int(os.environ['NUMBER_OF_PROCESSORS'])
                except (ValueError, KeyError):
                    num = 0

def get_command_line():
    '''
    Returns prefix of command line used for spawning a child process
    '''
    if process.current_process()._identity == () and is_forking(sys.argv):
        raise RuntimeError('''
        Attempt to start a new process before the current process
        has finished its bootstrapping phase.

        This probably means that have forgotten to use the proper
        idiom in the main module:

            if __name__ == '__main__':
                freeze_support()
                ...

        The "freeze_support()" line can be omitted if the program
        is not going to be frozen to produce a Windows executable.''')

    if getattr(sys, 'frozen', False):
        return [sys.executable, '--billiard-fork']

def get_command_line():
    '''
    Returns prefix of command line used for spawning a child process
    '''
    if process.current_process()._identity == () and is_forking(sys.argv):
        raise RuntimeError('''
        Attempt to start a new process before the current process
        has finished its bootstrapping phase.

        This probably means that have forgotten to use the proper
        idiom in the main module:

            if __name__ == '__main__':
                freeze_support()
                ...

        The "freeze_support()" line can be omitted if the program
        is not going to be frozen to produce a Windows executable.''')

    if getattr(sys, 'frozen', False):
        return [sys.executable, '--billiard-fork']

def __init__(self, address=None, authkey=None, serializer='pickle',
                 ctx=None):
        if authkey is None:
            authkey = process.current_process().authkey
        self._address = address     # XXX not final address if eg ('', 0)
        self._authkey = process.AuthenticationString(authkey)
        self._state = State()
        self._state.value = State.INITIAL
        self._serializer = serializer
        self._Listener, self._Client = listener_client[serializer]
        self._ctx = ctx or get_context()

def get_connection(ident):
        '''Return connection from which to receive identified resource.'''
        from .connection import Client
        address, key = ident
        c = Client(address, authkey=process.current_process().authkey)
        c.send((key, os.getpid()))
        return c

def _main(fd):
    _Django_old_layout_hack__load()
    with io.open(fd, 'rb', closefd=True) as from_parent:
        process.current_process()._inheriting = True
        try:
            preparation_data = pickle.load(from_parent)
            prepare(preparation_data)
            _setup_logging_in_child_hack()
            self = pickle.load(from_parent)
        finally:
            del process.current_process()._inheriting
    return self._bootstrap()

def __init__(self, registry, address, authkey, serializer):
        assert isinstance(authkey, bytes)
        self.registry = registry
        self.authkey = process.AuthenticationString(authkey)
        Listener, Client = listener_client[serializer]

        # do authentication later
        self.listener = Listener(address=address, backlog=16)
        self.address = self.listener.address

        self.id_to_obj = {'0': (None, ())}
        self.id_to_refcount = {}
        self.mutex = threading.RLock()

sys_argv=sys.argv,
        log_to_stderr=_log_to_stderr,
        orig_dir=process.ORIGINAL_DIR,
        authkey=process.current_process().authkey,
    )

    if _logger is not None:
        d['log_level'] = _logger.getEffectiveLevel()

    if not WINEXE and not WINSERVICE:
        main_path = getattr(sys.modules['__main__'], '__file__', None)
        if not main_path and sys.argv[0] not in ('', '-c'):
            main_path = sys.argv[0]
        if main_path is not None:
            if (not os.path.isabs(main_path) and
                    process.ORIGINAL_DIR is not None):
                main_path = os.path.join(process.ORIGINAL_DIR, main_path)
            d['main_path'] = os.path.normpath(main_path)

    return d

def main(listener_fd, alive_r, preload, main_path=None, sys_path=None):
    '''Run forkserver.'''
    if preload:
        if '__main__' in preload and main_path is not None:
            process.current_process()._inheriting = True
            try:
                spawn.import_main_path(main_path)
            finally:
                del process.current_process()._inheriting
        for modname in preload:
            try:
                __import__(modname)
            except ImportError:
                pass

    # close sys.stdin
    if sys.stdin is not None:
        try:
            sys.stdin.close()
            sys.stdin = open(os.devnull)
        except (OSError, ValueError):

def __repr__(self):
        try:
            if self._semlock._is_mine():
                name = process.current_process().name
                if threading.current_thread().name != 'MainThread':
                    name += '|' + threading.current_thread().name
                count = self._semlock._count()
            elif self._semlock._get_value() == 1:
                name, count = 'None', 0
            elif self._semlock._count() > 0:
                name, count = 'SomeOtherThread', 'nonzero'
            else:
                name, count = 'SomeOtherProcess', 'nonzero'
        except Exception:
            name, count = 'unknown', 'unknown'
        return '<%s(%s, %s)>' % (self.__class__.__name__, name, count)