How to use the mitogen.parent function in mitogen

import inspect
import sys
import zlib

import mitogen.fakessh
import mitogen.fork
import mitogen.master
import mitogen.minify
import mitogen.parent
import mitogen.select
import mitogen.service
import mitogen.ssh
import mitogen.sudo

router = mitogen.master.Router()
context = mitogen.parent.Context(router, 0)
stream = mitogen.ssh.Stream(router, 0, max_message_size=0, hostname='foo')

print('SSH command size: %s' % (len(' '.join(stream.get_boot_command())),))
print('Preamble size: %s (%.2fKiB)' % (
    len(stream.get_preamble()),
    len(stream.get_preamble()) / 1024.0,
))
if '--dump' in sys.argv:
    print(zlib.decompress(stream.get_preamble()))
    exit()


print(
    '                           '
    ' '
    '  Original   '

elif state == 'in_plain':
                line, nl, buf = bytes_partition(buf, b('\n'))
                yield line + nl, not (nl or buf)
                if nl:
                    state = 'start_of_line'


class PasswordError(mitogen.core.StreamError):
    pass


class HostKeyError(mitogen.core.StreamError):
    pass


class Stream(mitogen.parent.Stream):
    child_is_immediate_subprocess = False

    #: Default to whatever is available as 'python' on the remote machine,
    #: overriding sys.executable use.
    python_path = 'python'

    #: Number of -v invocations to pass on command line.
    ssh_debug_level = 0

    #: The path to the SSH binary.
    ssh_path = 'ssh'

    hostname = None
    username = None
    port = None

def _convert_exit_status(status):
    """
    Convert a :func:`os.waitpid`-style exit status to a :mod:`subprocess` style
    exit status.
    """
    if os.WIFEXITED(status):
        return os.WEXITSTATUS(status)
    elif os.WIFSIGNALED(status):
        return -os.WTERMSIG(status)
    elif os.WIFSTOPPED(status):
        return -os.WSTOPSIG(status)


class Process(mitogen.parent.Process):
    def poll(self):
        try:
            pid, status = os.waitpid(self.pid, os.WNOHANG)
        except OSError:
            e = sys.exc_info()[1]
            if e.args[0] == errno.ECHILD:
                LOG.warn('%r: waitpid(%r) produced ECHILD', self, self.pid)
                return
            raise

        if not pid:
            return
        return _convert_exit_status(status)


class Options(mitogen.parent.Options):

try:
        proc = subprocess.Popen(
            args=args,
            stdout=subprocess.PIPE,
            stderr=subprocess.STDOUT
        )
    except OSError:
        e = sys.exc_info()[1]
        raise Error('could not execute %s: %s', argv, e)

    output, _ = proc.communicate()
    if not proc.returncode:
        return output.decode('utf-8', 'replace')

    raise Error("%s exitted with status %d: %s",
                mitogen.parent.Argv(args), proc.returncode, output)

def create_child(self, args):
        return mitogen.parent.create_child(args, preexec_fn=self.preexec_fn)

def get_boot_command(self):
        argv = mitogen.parent.Argv(super(Stream, self).get_boot_command())
        return [self.su_path, self.username, '-c', str(argv)]

def _configure_context(cls, econtext):
        mitogen.parent.upgrade_router(econtext)
        econtext.debugger = cls(econtext.router)

def upgrade(self):
        self.id_allocator = IdAllocator(self)
        self.responder = ModuleResponder(self)
        self.log_forwarder = LogForwarder(self)
        self.route_monitor = mitogen.parent.RouteMonitor(router=self)
        self.add_handler(  # TODO: cutpaste.
            fn=self._on_detaching,
            handle=mitogen.core.DETACHING,
            persist=True,
        )

container = None
    username = None
    buildah_path = 'buildah'

    def __init__(self, container=None, buildah_path=None, username=None,
                 **kwargs):
        super(Options, self).__init__(**kwargs)
        assert container is not None
        self.container = container
        if buildah_path:
            self.buildah_path = buildah_path
        if username:
            self.username = username


class Connection(mitogen.parent.Connection):
    options_class = Options
    child_is_immediate_subprocess = False

    # TODO: better way of capturing errors such as "No such container."
    create_child_args = {
        'merge_stdio': True
    }

    def _get_name(self):
        return u'buildah.' + self.options.container

    def get_boot_command(self):
        args = [self.options.buildah_path, 'run']
        if self.options.username:
            args += ['--user=' + self.options.username]
        args += ['--', self.options.container]

def _accept_client(self, sock):
        sock.setblocking(True)
        try:
            pid, = struct.unpack('>L', sock.recv(4))
        except (struct.error, socket.error):
            LOG.error('%r: failed to read remote identity: %s',
                      self, sys.exc_info()[1])
            return

        context_id = self._router.id_allocator.allocate()
        context = mitogen.parent.Context(self._router, context_id)
        stream = mitogen.core.Stream(self._router, context_id)
        stream.name = u'unix_client.%d' % (pid,)
        stream.auth_id = mitogen.context_id
        stream.is_privileged = True

        try:
            sock.send(struct.pack('>LLL', context_id, mitogen.context_id,
                                  os.getpid()))
        except socket.error:
            LOG.error('%r: failed to assign identity to PID %d: %s',
                      self, pid, sys.exc_info()[1])
            return

        LOG.debug('%r: accepted %r', self, stream)
        stream.accept(sock.fileno(), sock.fileno())
        self._router.register(context, stream)