Current File : //data/old/usr/lib64/python3.4/site-packages/aiohttp/connector.py
import asyncio
import functools
import sys
import traceback
import warnings
from collections import defaultdict
from hashlib import md5, sha1, sha256
from itertools import cycle, islice
from time import monotonic
from types import MappingProxyType
from . import hdrs, helpers
from .client_exceptions import (ClientConnectionError,
ClientConnectorCertificateError,
ClientConnectorError, ClientConnectorSSLError,
ClientHttpProxyError,
ClientProxyConnectionError,
ServerFingerprintMismatch, certificate_errors,
ssl_errors)
from .client_proto import ResponseHandler
from .client_reqrep import ClientRequest
from .helpers import SimpleCookie, is_ip_address, noop, sentinel
from .locks import EventResultOrError
from .log import client_logger
from .resolver import DefaultResolver
try:
import ssl
except ImportError: # pragma: no cover
ssl = None
__all__ = ('BaseConnector', 'TCPConnector', 'UnixConnector')
HASHFUNC_BY_DIGESTLEN = {
16: md5,
20: sha1,
32: sha256,
}
class Connection:
_source_traceback = None
_transport = None
def __init__(self, connector, key, protocol, loop):
self._key = key
self._connector = connector
self._loop = loop
self._protocol = protocol
self._callbacks = []
if loop.get_debug():
self._source_traceback = traceback.extract_stack(sys._getframe(1))
def __repr__(self):
return 'Connection<{}>'.format(self._key)
def __del__(self, _warnings=warnings):
if self._protocol is not None:
_warnings.warn('Unclosed connection {!r}'.format(self),
ResourceWarning)
if self._loop.is_closed():
return
self._connector._release(
self._key, self._protocol, should_close=True)
context = {'client_connection': self,
'message': 'Unclosed connection'}
if self._source_traceback is not None:
context['source_traceback'] = self._source_traceback
self._loop.call_exception_handler(context)
@property
def loop(self):
return self._loop
@property
def transport(self):
return self._protocol.transport
@property
def protocol(self):
return self._protocol
@property
def writer(self):
return self._protocol.writer
def add_callback(self, callback):
if callback is not None:
self._callbacks.append(callback)
def _notify_release(self):
callbacks, self._callbacks = self._callbacks[:], []
for cb in callbacks:
try:
cb()
except:
pass
def close(self):
self._notify_release()
if self._protocol is not None:
self._connector._release(
self._key, self._protocol, should_close=True)
self._protocol = None
def release(self):
self._notify_release()
if self._protocol is not None:
self._connector._release(
self._key, self._protocol,
should_close=self._protocol.should_close)
self._protocol = None
def detach(self):
self._notify_release()
if self._protocol is not None:
self._connector._release_acquired(self._protocol)
self._protocol = None
@property
def closed(self):
return self._protocol is None or not self._protocol.is_connected()
class _TransportPlaceholder:
""" placeholder for BaseConnector.connect function """
def close(self):
pass
class BaseConnector(object):
"""Base connector class.
keepalive_timeout - (optional) Keep-alive timeout.
force_close - Set to True to force close and do reconnect
after each request (and between redirects).
limit - The total number of simultaneous connections.
limit_per_host - Number of simultaneous connections to one host.
enable_cleanup_closed - Enables clean-up closed ssl transports.
Disabled by default.
loop - Optional event loop.
"""
_closed = True # prevent AttributeError in __del__ if ctor was failed
_source_traceback = None
# abort transport after 2 seconds (cleanup broken connections)
_cleanup_closed_period = 2.0
def __init__(self, *, keepalive_timeout=sentinel,
force_close=False, limit=100, limit_per_host=0,
enable_cleanup_closed=False, loop=None):
if force_close:
if keepalive_timeout is not None and \
keepalive_timeout is not sentinel:
raise ValueError('keepalive_timeout cannot '
'be set if force_close is True')
else:
if keepalive_timeout is sentinel:
keepalive_timeout = 15.0
if loop is None:
loop = asyncio.get_event_loop()
self._closed = False
if loop.get_debug():
self._source_traceback = traceback.extract_stack(sys._getframe(1))
self._conns = {}
self._limit = limit
self._limit_per_host = limit_per_host
self._acquired = set()
self._acquired_per_host = defaultdict(set)
self._keepalive_timeout = keepalive_timeout
self._force_close = force_close
self._waiters = defaultdict(list)
self._loop = loop
self._factory = functools.partial(ResponseHandler, loop=loop)
self.cookies = SimpleCookie()
# start keep-alive connection cleanup task
self._cleanup_handle = None
# start cleanup closed transports task
self._cleanup_closed_handle = None
self._cleanup_closed_disabled = not enable_cleanup_closed
self._cleanup_closed_transports = []
self._cleanup_closed()
def __del__(self, _warnings=warnings):
if self._closed:
return
if not self._conns:
return
conns = [repr(c) for c in self._conns.values()]
self.close()
_warnings.warn("Unclosed connector {!r}".format(self),
ResourceWarning)
context = {'connector': self,
'connections': conns,
'message': 'Unclosed connector'}
if self._source_traceback is not None:
context['source_traceback'] = self._source_traceback
self._loop.call_exception_handler(context)
def __enter__(self):
return self
def __exit__(self, *exc):
self.close()
@property
def force_close(self):
"""Ultimately close connection on releasing if True."""
return self._force_close
@property
def limit(self):
"""The total number for simultaneous connections.
If limit is 0 the connector has no limit.
The default limit size is 100.
"""
return self._limit
@property
def limit_per_host(self):
"""The limit_per_host for simultaneous connections
to the same endpoint.
Endpoints are the same if they are have equal
(host, port, is_ssl) triple.
"""
return self._limit_per_host
def _cleanup(self):
"""Cleanup unused transports."""
if self._cleanup_handle:
self._cleanup_handle.cancel()
now = self._loop.time()
timeout = self._keepalive_timeout
if self._conns:
connections = {}
deadline = now - timeout
for key, conns in self._conns.items():
alive = []
for proto, use_time in conns:
if proto.is_connected():
if use_time - deadline < 0:
transport = proto.close()
if (key[-1] and not self._cleanup_closed_disabled):
self._cleanup_closed_transports.append(
transport)
else:
alive.append((proto, use_time))
if alive:
connections[key] = alive
self._conns = connections
if self._conns:
self._cleanup_handle = helpers.weakref_handle(
self, '_cleanup', timeout, self._loop)
def _drop_acquired_per_host(self, key, val):
acquired_per_host = self._acquired_per_host
if key not in acquired_per_host:
return
conns = acquired_per_host[key]
conns.remove(val)
if not conns:
del self._acquired_per_host[key]
def _cleanup_closed(self):
"""Double confirmation for transport close.
Some broken ssl servers may leave socket open without proper close.
"""
if self._cleanup_closed_handle:
self._cleanup_closed_handle.cancel()
for transport in self._cleanup_closed_transports:
if transport is not None:
transport.abort()
self._cleanup_closed_transports = []
if not self._cleanup_closed_disabled:
self._cleanup_closed_handle = helpers.weakref_handle(
self, '_cleanup_closed',
self._cleanup_closed_period, self._loop)
def close(self):
"""Close all opened transports."""
if self._closed:
return
self._closed = True
try:
if self._loop.is_closed():
return noop()
# cancel cleanup task
if self._cleanup_handle:
self._cleanup_handle.cancel()
# cancel cleanup close task
if self._cleanup_closed_handle:
self._cleanup_closed_handle.cancel()
for data in self._conns.values():
for proto, t0 in data:
proto.close()
for proto in self._acquired:
proto.close()
for transport in self._cleanup_closed_transports:
if transport is not None:
transport.abort()
finally:
self._conns.clear()
self._acquired.clear()
self._waiters.clear()
self._cleanup_handle = None
self._cleanup_closed_transports.clear()
self._cleanup_closed_handle = None
@property
def closed(self):
"""Is connector closed.
A readonly property.
"""
return self._closed
@asyncio.coroutine
def connect(self, req):
"""Get from pool or create new connection."""
key = req.connection_key
if self._limit:
# total calc available connections
available = self._limit - len(self._acquired)
# check limit per host
if (self._limit_per_host and available > 0 and
key in self._acquired_per_host):
available = self._limit_per_host - len(
self._acquired_per_host.get(key))
elif self._limit_per_host and key in self._acquired_per_host:
# check limit per host
available = self._limit_per_host - len(
self._acquired_per_host.get(key))
else:
available = 1
# Wait if there are no available connections.
if available <= 0:
fut = helpers.create_future(self._loop)
# This connection will now count towards the limit.
waiters = self._waiters[key]
waiters.append(fut)
try:
yield from fut
finally:
# remove a waiter even if it was cancelled
waiters.remove(fut)
if not waiters:
del self._waiters[key]
proto = self._get(key)
if proto is None:
placeholder = _TransportPlaceholder()
self._acquired.add(placeholder)
self._acquired_per_host[key].add(placeholder)
try:
proto = yield from self._create_connection(req)
if self._closed:
proto.close()
raise ClientConnectionError("Connector is closed.")
except:
# signal to waiter
if key in self._waiters:
for waiter in self._waiters[key]:
if not waiter.done():
waiter.set_result(None)
break
raise
finally:
if not self._closed:
self._acquired.remove(placeholder)
self._drop_acquired_per_host(key, placeholder)
self._acquired.add(proto)
self._acquired_per_host[key].add(proto)
return Connection(self, key, proto, self._loop)
def _get(self, key):
try:
conns = self._conns[key]
except KeyError:
return None
t1 = self._loop.time()
while conns:
proto, t0 = conns.pop()
if proto.is_connected():
if t1 - t0 > self._keepalive_timeout:
transport = proto.close()
# only for SSL transports
if key[-1] and not self._cleanup_closed_disabled:
self._cleanup_closed_transports.append(transport)
else:
if not conns:
# The very last connection was reclaimed: drop the key
del self._conns[key]
return proto
# No more connections: drop the key
del self._conns[key]
return None
def _release_waiter(self):
# always release only one waiter
if self._limit:
# if we have limit and we have available
if self._limit - len(self._acquired) > 0:
for key, waiters in self._waiters.items():
if waiters:
if not waiters[0].done():
waiters[0].set_result(None)
break
elif self._limit_per_host:
# if we have dont have limit but have limit per host
# then release first available
for key, waiters in self._waiters.items():
if waiters:
if not waiters[0].done():
waiters[0].set_result(None)
break
def _release_acquired(self, key, proto):
if self._closed:
# acquired connection is already released on connector closing
return
try:
self._acquired.remove(proto)
self._drop_acquired_per_host(key, proto)
except KeyError: # pragma: no cover
# this may be result of undetermenistic order of objects
# finalization due garbage collection.
pass
else:
self._release_waiter()
def _release(self, key, protocol, *, should_close=False):
if self._closed:
# acquired connection is already released on connector closing
return
self._release_acquired(key, protocol)
if self._force_close:
should_close = True
if should_close or protocol.should_close:
transport = protocol.close()
if key[-1] and not self._cleanup_closed_disabled:
self._cleanup_closed_transports.append(transport)
else:
conns = self._conns.get(key)
if conns is None:
conns = self._conns[key] = []
conns.append((protocol, self._loop.time()))
if self._cleanup_handle is None:
self._cleanup_handle = helpers.weakref_handle(
self, '_cleanup', self._keepalive_timeout, self._loop)
@asyncio.coroutine
def _create_connection(self, req):
raise NotImplementedError()
_SSL_OP_NO_COMPRESSION = getattr(ssl, "OP_NO_COMPRESSION", 0)
class _DNSCacheTable:
def __init__(self, ttl=None):
self._addrs = {}
self._addrs_rr = {}
self._timestamps = {}
self._ttl = ttl
def __contains__(self, host):
return host in self._addrs
@property
def addrs(self):
return self._addrs
def add(self, host, addrs):
self._addrs[host] = addrs
self._addrs_rr[host] = cycle(addrs)
if self._ttl:
self._timestamps[host] = monotonic()
def remove(self, host):
self._addrs.pop(host, None)
self._addrs_rr.pop(host, None)
if self._ttl:
self._timestamps.pop(host, None)
def clear(self):
self._addrs.clear()
self._addrs_rr.clear()
self._timestamps.clear()
def next_addrs(self, host):
loop = self._addrs_rr[host]
addrs = list(islice(loop, len(self._addrs[host])))
# Consume one more element to shift internal state of `cycle`
next(loop)
return addrs
def expired(self, host):
if self._ttl is None:
return False
return (
self._timestamps[host] + self._ttl
) < monotonic()
class TCPConnector(BaseConnector):
"""TCP connector.
verify_ssl - Set to True to check ssl certifications.
fingerprint - Pass the binary md5, sha1, or sha256
digest of the expected certificate in DER format to verify
that the certificate the server presents matches. See also
https://en.wikipedia.org/wiki/Transport_Layer_Security#Certificate_pinning
resolve - (Deprecated) Set to True to do DNS lookup for
host name.
resolver - Enable DNS lookups and use this
resolver
use_dns_cache - Use memory cache for DNS lookups.
ttl_dns_cache - Max seconds having cached a DNS entry, None forever.
family - socket address family
local_addr - local tuple of (host, port) to bind socket to
keepalive_timeout - (optional) Keep-alive timeout.
force_close - Set to True to force close and do reconnect
after each request (and between redirects).
limit - The total number of simultaneous connections.
limit_per_host - Number of simultaneous connections to one host.
enable_cleanup_closed - Enables clean-up closed ssl transports.
Disabled by default.
loop - Optional event loop.
"""
def __init__(self, *, verify_ssl=True, fingerprint=None,
resolve=sentinel, use_dns_cache=True, ttl_dns_cache=10,
family=0, ssl_context=None, local_addr=None,
resolver=None, keepalive_timeout=sentinel,
force_close=False, limit=100, limit_per_host=0,
enable_cleanup_closed=False, loop=None):
super().__init__(keepalive_timeout=keepalive_timeout,
force_close=force_close,
limit=limit, limit_per_host=limit_per_host,
enable_cleanup_closed=enable_cleanup_closed,
loop=loop)
if not verify_ssl and ssl_context is not None:
raise ValueError(
"Either disable ssl certificate validation by "
"verify_ssl=False or specify ssl_context, not both.")
self._verify_ssl = verify_ssl
if fingerprint:
digestlen = len(fingerprint)
hashfunc = HASHFUNC_BY_DIGESTLEN.get(digestlen)
if not hashfunc:
raise ValueError('fingerprint has invalid length')
elif hashfunc is md5 or hashfunc is sha1:
warnings.warn('md5 and sha1 are insecure and deprecated. '
'Use sha256.',
DeprecationWarning, stacklevel=2)
client_logger.warn('md5 and sha1 are insecure and deprecated. '
'Use sha256.')
self._hashfunc = hashfunc
self._fingerprint = fingerprint
if resolver is None:
resolver = DefaultResolver(loop=self._loop)
self._resolver = resolver
self._use_dns_cache = use_dns_cache
self._cached_hosts = _DNSCacheTable(ttl=ttl_dns_cache)
self._throttle_dns_events = {}
self._ssl_context = ssl_context
self._family = family
self._local_addr = local_addr
def close(self):
"""Close all ongoing DNS calls."""
for ev in self._throttle_dns_events.values():
ev.cancel()
super().close()
@property
def verify_ssl(self):
"""Do check for ssl certifications?"""
return self._verify_ssl
@property
def fingerprint(self):
"""Expected ssl certificate fingerprint."""
return self._fingerprint
@property
def ssl_context(self):
"""SSLContext instance for https requests.
Lazy property, creates context on demand.
"""
if ssl is None: # pragma: no cover
raise RuntimeError('SSL is not supported.')
if self._ssl_context is None:
if not self._verify_ssl:
sslcontext = ssl.SSLContext(ssl.PROTOCOL_SSLv23)
sslcontext.options |= ssl.OP_NO_SSLv2
sslcontext.options |= ssl.OP_NO_SSLv3
sslcontext.options |= _SSL_OP_NO_COMPRESSION
sslcontext.set_default_verify_paths()
else:
sslcontext = ssl.create_default_context()
self._ssl_context = sslcontext
return self._ssl_context
@property
def family(self):
"""Socket family like AF_INET."""
return self._family
@property
def use_dns_cache(self):
"""True if local DNS caching is enabled."""
return self._use_dns_cache
@property
def cached_hosts(self):
"""Read-only dict of cached DNS record."""
return MappingProxyType(self._cached_hosts.addrs)
def clear_dns_cache(self, host=None, port=None):
"""Remove specified host/port or clear all dns local cache."""
if host is not None and port is not None:
self._cached_hosts.remove((host, port))
elif host is not None or port is not None:
raise ValueError("either both host and port "
"or none of them are allowed")
else:
self._cached_hosts.clear()
@asyncio.coroutine
def _resolve_host(self, host, port):
if is_ip_address(host):
return [{'hostname': host, 'host': host, 'port': port,
'family': self._family, 'proto': 0, 'flags': 0}]
if not self._use_dns_cache:
return (yield from self._resolver.resolve(
host, port, family=self._family))
key = (host, port)
if (key in self._cached_hosts) and\
(not self._cached_hosts.expired(key)):
return self._cached_hosts.next_addrs(key)
if key in self._throttle_dns_events:
yield from self._throttle_dns_events[key].wait()
else:
self._throttle_dns_events[key] = \
EventResultOrError(self._loop)
try:
addrs = yield from \
asyncio.shield(self._resolver.resolve(host,
port,
family=self._family),
loop=self._loop)
self._cached_hosts.add(key, addrs)
self._throttle_dns_events[key].set()
except Exception as e:
# any DNS exception, independently of the implementation
# is set for the waiters to raise the same exception.
self._throttle_dns_events[key].set(exc=e)
raise
finally:
self._throttle_dns_events.pop(key)
return self._cached_hosts.next_addrs(key)
@asyncio.coroutine
def _create_connection(self, req):
"""Create connection.
Has same keyword arguments as BaseEventLoop.create_connection.
"""
if req.proxy:
_, proto = yield from self._create_proxy_connection(req)
else:
_, proto = yield from self._create_direct_connection(req)
return proto
def _get_ssl_context(self, req):
"""Logic to get the correct SSL context
0. if req.ssl is false, return None
1. if ssl_context is specified in req, use it
2. if _ssl_context is specified in self, use it
3. otherwise:
1. if verify_ssl is not specified in req, use self.ssl_context
(will generate a default context according to self.verify_ssl)
2. if verify_ssl is True in req, generate a default SSL context
3. if verify_ssl is False in req, generate a SSL context that
won't verify
"""
if req.ssl:
sslcontext = req.ssl_context or self._ssl_context
if not sslcontext:
if req.verify_ssl is None:
sslcontext = self.ssl_context
elif req.verify_ssl:
sslcontext = ssl.create_default_context()
else:
sslcontext = ssl.SSLContext(ssl.PROTOCOL_SSLv23)
sslcontext.options |= ssl.OP_NO_SSLv2
sslcontext.options |= ssl.OP_NO_SSLv3
sslcontext.options |= _SSL_OP_NO_COMPRESSION
sslcontext.set_default_verify_paths()
else:
sslcontext = None
return sslcontext
def _get_fingerprint_and_hashfunc(self, req):
if req.fingerprint:
return (req.fingerprint, req._hashfunc)
elif self.fingerprint:
return (self.fingerprint, self._hashfunc)
else:
return (None, None)
@asyncio.coroutine
def _wrap_create_connection(self, *args,
req, client_error=ClientConnectorError,
**kwargs):
try:
return (yield from self._loop.create_connection(*args, **kwargs))
except certificate_errors as exc:
raise ClientConnectorCertificateError(
req.connection_key, exc) from exc
except ssl_errors as exc:
raise ClientConnectorSSLError(req.connection_key, exc) from exc
except OSError as exc:
raise client_error(req.connection_key, exc) from exc
@asyncio.coroutine
def _create_direct_connection(self, req,
*, client_error=ClientConnectorError):
sslcontext = self._get_ssl_context(req)
fingerprint, hashfunc = self._get_fingerprint_and_hashfunc(req)
try:
hosts = yield from self._resolve_host(req.url.raw_host, req.port)
except OSError as exc:
# in case of proxy it is not ClientProxyConnectionError
# it is problem of resolving proxy ip itself
raise ClientConnectorError(req.connection_key, exc) from exc
last_exc = None
for hinfo in hosts:
host = hinfo['host']
port = hinfo['port']
try:
transp, proto = yield from self._wrap_create_connection(
self._factory, host, port,
ssl=sslcontext, family=hinfo['family'],
proto=hinfo['proto'], flags=hinfo['flags'],
server_hostname=hinfo['hostname'] if sslcontext else None,
local_addr=self._local_addr,
req=req, client_error=client_error)
except ClientConnectorError as exc:
last_exc = exc
continue
has_cert = transp.get_extra_info('sslcontext')
if has_cert and fingerprint:
sock = transp.get_extra_info('socket')
if not hasattr(sock, 'getpeercert'):
# Workaround for asyncio 3.5.0
# Starting from 3.5.1 version
# there is 'ssl_object' extra info in transport
sock = transp._ssl_protocol._sslpipe.ssl_object
# gives DER-encoded cert as a sequence of bytes (or None)
cert = sock.getpeercert(binary_form=True)
assert cert
got = hashfunc(cert).digest()
expected = fingerprint
if got != expected:
transp.close()
if not self._cleanup_closed_disabled:
self._cleanup_closed_transports.append(transp)
last_exc = ServerFingerprintMismatch(
expected, got, host, port)
continue
return transp, proto
else:
raise last_exc
@asyncio.coroutine
def _create_proxy_connection(self, req):
headers = {}
if req.proxy_headers is not None:
headers = req.proxy_headers
headers[hdrs.HOST] = req.headers[hdrs.HOST]
proxy_req = ClientRequest(
hdrs.METH_GET, req.proxy,
headers=headers,
auth=req.proxy_auth,
loop=self._loop,
verify_ssl=req.verify_ssl,
fingerprint=req.fingerprint,
ssl_context=req.ssl_context)
# create connection to proxy server
transport, proto = yield from self._create_direct_connection(
proxy_req, client_error=ClientProxyConnectionError)
auth = proxy_req.headers.pop(hdrs.AUTHORIZATION, None)
if auth is not None:
if not req.ssl:
req.headers[hdrs.PROXY_AUTHORIZATION] = auth
else:
proxy_req.headers[hdrs.PROXY_AUTHORIZATION] = auth
if req.ssl:
sslcontext = self._get_ssl_context(req)
# For HTTPS requests over HTTP proxy
# we must notify proxy to tunnel connection
# so we send CONNECT command:
# CONNECT www.python.org:443 HTTP/1.1
# Host: www.python.org
#
# next we must do TLS handshake and so on
# to do this we must wrap raw socket into secure one
# asyncio handles this perfectly
proxy_req.method = hdrs.METH_CONNECT
proxy_req.url = req.url
key = (req.host, req.port, req.ssl)
conn = Connection(self, key, proto, self._loop)
proxy_resp = proxy_req.send(conn)
try:
resp = yield from proxy_resp.start(conn, True)
except:
proxy_resp.close()
conn.close()
raise
else:
conn._protocol = None
conn._transport = None
try:
if resp.status != 200:
raise ClientHttpProxyError(
proxy_resp.request_info,
resp.history,
code=resp.status,
message=resp.reason,
headers=resp.headers)
rawsock = transport.get_extra_info('socket', default=None)
if rawsock is None:
raise RuntimeError(
"Transport does not expose socket instance")
# Duplicate the socket, so now we can close proxy transport
rawsock = rawsock.dup()
finally:
transport.close()
transport, proto = yield from self._wrap_create_connection(
self._factory, ssl=sslcontext, sock=rawsock,
server_hostname=req.host,
req=req)
finally:
proxy_resp.close()
return transport, proto
class UnixConnector(BaseConnector):
"""Unix socket connector.
path - Unix socket path.
keepalive_timeout - (optional) Keep-alive timeout.
force_close - Set to True to force close and do reconnect
after each request (and between redirects).
limit - The total number of simultaneous connections.
limit_per_host - Number of simultaneous connections to one host.
loop - Optional event loop.
Usage:
>>> conn = UnixConnector(path='/path/to/socket')
>>> session = ClientSession(connector=conn)
>>> resp = yield from session.get('http://python.org')
"""
def __init__(self, path, force_close=False, keepalive_timeout=sentinel,
limit=100, limit_per_host=0, loop=None):
super().__init__(force_close=force_close,
keepalive_timeout=keepalive_timeout,
limit=limit, limit_per_host=limit_per_host, loop=loop)
self._path = path
@property
def path(self):
"""Path to unix socket."""
return self._path
@asyncio.coroutine
def _create_connection(self, req):
try:
_, proto = yield from self._loop.create_unix_connection(
self._factory, self._path)
except OSError as exc:
raise ClientConnectorError(req.connection_key, exc) from exc
return proto
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