How to use the rpyc.lib.safe_import function in rpyc

import time
import threading  # noqa: F401
import errno
import logging
from contextlib import closing
try:
    import Queue
except ImportError:
    import queue as Queue
from rpyc.core import SocketStream, Channel
from rpyc.utils.registry import UDPRegistryClient
from rpyc.utils.authenticators import AuthenticationError
from rpyc.lib import safe_import, spawn, spawn_waitready
from rpyc.lib.compat import poll, get_exc_errno
signal = safe_import("signal")
gevent = safe_import("gevent")


class Server(object):
    """Base server implementation

    :param service: the :class:`~rpyc.core.service.Service` to expose
    :param hostname: the host to bind to. Default is IPADDR_ANY, but you may
                     want to restrict it only to ``localhost`` in some setups
    :param ipv6: whether to create an IPv6 or IPv4 socket. The default is IPv4
    :param port: the TCP port to bind to
    :param backlog: the socket's backlog (passed to ``listen()``)
    :param reuse_addr: whether or not to create the socket with the ``SO_REUSEADDR`` option set.
    :param authenticator: the :ref:`api-authenticators` to use. If ``None``, no authentication
                          is performed.
    :param registrar: the :class:`~rpyc.utils.registry.RegistryClient` to use.
                          If ``None``, a default :class:`~rpyc.utils.registry.UDPRegistryClient`

raise AuthenticationError("wrong magic word")
        return sock, None

RPyC comes bundled with an authenticator for ``SSL`` (using certificates).
This authenticator, for instance, both verifies the peer's identity and wraps the
socket with an encrypted transport (which replaces the original socket).

Authenticators are used by :class:`~rpyc.utils.server.Server` to
validate an incoming connection. Using them is pretty trivial ::

    s = ThreadedServer(...., authenticator = magic_word_authenticator)
    s.start()
"""
import sys
from rpyc.lib import safe_import
ssl = safe_import("ssl")


class AuthenticationError(Exception):
    """raised to signal a failed authentication attempt"""
    pass


class SSLAuthenticator(object):
    """An implementation of the authenticator protocol for ``SSL``. The given
    socket is wrapped by ``ssl.wrap_socket`` and is validated based on
    certificates

    :param keyfile: the server's key file
    :param certfile: the server's certificate file
    :param ca_certs: the server's certificate authority file
    :param cert_reqs: the certificate requirements. By default, if ``ca_cert`` is

"""
An abstraction layer over OS-dependent file-like objects, that provides a
consistent view of a *duplex byte stream*.
"""
import sys
import os
import socket
import errno
from rpyc.lib import safe_import, Timeout, socket_backoff_connect
from rpyc.lib.compat import poll, select_error, BYTES_LITERAL, get_exc_errno, maxint  # noqa: F401
win32file = safe_import("win32file")
win32pipe = safe_import("win32pipe")
win32event = safe_import("win32event")


retry_errnos = (errno.EAGAIN, errno.EWOULDBLOCK)


class Stream(object):
    """Base Stream"""

    __slots__ = ()

    def close(self):
        """closes the stream, releasing any system resources associated with it"""
        raise NotImplementedError()

    @property
    def closed(self):

"""
An abstraction layer over OS-dependent file-like objects, that provides a 
consistent view of a *duplex byte stream*.
"""
import sys
import os
import socket
import time
import errno
from rpyc.lib import safe_import
from rpyc.lib.compat import select, select_error, BYTES_LITERAL, get_exc_errno, maxint
win32file = safe_import("win32file")
win32pipe = safe_import("win32pipe")
msvcrt = safe_import("msvcrt")
ssl = safe_import("ssl")


retry_errnos = (errno.EAGAIN, errno.EWOULDBLOCK)


class Stream(object):
    """Base Stream"""
    
    __slots__ = ()
    def close(self):
        """closes the stream, releasing any system resources associated with it"""
        raise NotImplementedError()
    @property

import os
import socket
import time
import threading
import errno
import logging
try:
    import Queue
except ImportError:
    import queue as Queue
from rpyc.core import SocketStream, Channel, Connection
from rpyc.utils.registry import UDPRegistryClient
from rpyc.utils.authenticators import AuthenticationError
from rpyc.lib import safe_import
from rpyc.lib.compat import poll, get_exc_errno
signal = safe_import("signal")



class Server(object):
    """Base server implementation
    
    :param service: the :class:`service ` to expose
    :param hostname: the host to bind to. Default is IPADDR_ANY, but you may 
                     want to restrict it only to ``localhost`` in some setups
    :param ipv6: whether to create an IPv6 or IPv4 socket. The default is IPv4
    :param port: the TCP port to bind to
    :param backlog: the socket's backlog (passed to ``listen()``)
    :param reuse_addr: whether or not to create the socket with the ``SO_REUSEADDR`` option set.
    :param socket_path: for Unix domain sockets - specifies the socket's path (filename); 
                        requires platform support for ``AF_UNIX``. This option is mutually
                        exclusive with ``hostname``, ``ipv6`` and ``port`` 

try:
    from thread import interrupt_main
except ImportError:
    try:
        from _thread import interrupt_main
    except ImportError:
        # assume jython (#83)
        from java.lang import System
        interrupt_main = System.exit

from rpyc.core.channel import Channel
from rpyc.core.stream import SocketStream, TunneledSocketStream, PipeStream
from rpyc.core.service import VoidService
from rpyc.utils.registry import UDPRegistryClient
from rpyc.lib import safe_import, spawn
ssl = safe_import("ssl")


class DiscoveryError(Exception):
    pass


# ------------------------------------------------------------------------------
# API
# ------------------------------------------------------------------------------
def connect_channel(channel, service=VoidService, config={}):
    """creates a connection over a given channel

    :param channel: the channel to use
    :param service: the local service to expose (defaults to Void)
    :param config: configuration dict

"""
An abstraction layer over OS-dependent file-like objects, that provides a 
consistent view of a *duplex byte stream*.
"""
import sys
import os
import socket
import time
import errno
from rpyc.lib import safe_import
from rpyc.lib.compat import select, select_error, BYTES_LITERAL, get_exc_errno, maxint
win32file = safe_import("win32file")
win32pipe = safe_import("win32pipe")
msvcrt = safe_import("msvcrt")
ssl = safe_import("ssl")


retry_errnos = (errno.EAGAIN, errno.EWOULDBLOCK)


class Stream(object):
    """Base Stream"""
    
    __slots__ = ()
    def close(self):
        """closes the stream, releasing any system resources associated with it"""
        raise NotImplementedError()
    @property
    def closed(self):

"""
An abstraction layer over OS-dependent file-like objects, that provides a
consistent view of a *duplex byte stream*.
"""
import sys
import os
import socket
import errno
from rpyc.lib import safe_import, Timeout, socket_backoff_connect
from rpyc.lib.compat import poll, select_error, BYTES_LITERAL, get_exc_errno, maxint  # noqa: F401
win32file = safe_import("win32file")
win32pipe = safe_import("win32pipe")
win32event = safe_import("win32event")


retry_errnos = (errno.EAGAIN, errno.EWOULDBLOCK)


class Stream(object):
    """Base Stream"""

    __slots__ = ()

    def close(self):
        """closes the stream, releasing any system resources associated with it"""
        raise NotImplementedError()

import os
from subprocess import Popen, PIPE
from rpyc.lib import safe_import
from rpyc.lib.compat import BYTES_LITERAL
signal = safe_import("signal")

# modified from the stdlib pipes module for windows
_safechars = 'abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ0123456789!@%_-+=:,./'
_funnychars = '"`$\\'
def shquote(text):
    if not text:
        return "''"
    for c in text:
        if c not in _safechars:
            break
    else:
        return text
    if "'" not in text:
        return "'" + text + "'"
    def escaped(c):
        if c in _funnychars:

"""
An abstraction layer over OS-dependent file-like objects, that provides a 
consistent view of a *duplex byte stream*.
"""
import sys
import os
import socket
import time
import errno
from rpyc.lib import safe_import
from rpyc.lib.compat import select, select_error, BYTES_LITERAL, get_exc_errno, maxint
win32file = safe_import("win32file")
win32pipe = safe_import("win32pipe")
msvcrt = safe_import("msvcrt")
ssl = safe_import("ssl")


retry_errnos = (errno.EAGAIN, errno.EWOULDBLOCK)


class Stream(object):
    """Base Stream"""
    
    __slots__ = ()
    def close(self):
        """closes the stream, releasing any system resources associated with it"""
        raise NotImplementedError()
    @property
    def closed(self):
        """tests whether the stream is closed or not"""