anyio: asyncio CancelledError raised from SSLWantReadError handler in _call_sslobject_method

In an async Python application, I get the following traceback:

Traceback (most recent call last):
  File "python3.10/site-packages/anyio/streams/tls.py", line 130, in _call_sslobject_method
    result = func(*args)
  File "/usr/lib/python3.10/ssl.py", line 917, in read
    v = self._sslobj.read(len)
ssl.SSLWantReadError: The operation did not complete (read) (_ssl.c:2548)

During handling of the above exception, another exception occurred:

Traceback (most recent call last):
  File "python3.10/site-packages/httpcore/backends/asyncio.py", line 34, in read
    return await self._stream.receive(max_bytes=max_bytes)
  File "python3.10/site-packages/anyio/streams/tls.py", line 195, in receive
    data = await self._call_sslobject_method(self._ssl_object.read, max_bytes)
  File "python3.10/site-packages/anyio/streams/tls.py", line 137, in _call_sslobject_method
    data = await self.transport_stream.receive()
  File "python3.10/site-packages/anyio/_backends/_asyncio.py", line 1265, in receive
    await self._protocol.read_event.wait()
  File "/usr/lib/python3.10/asyncio/locks.py", line 214, in wait
    await fut
asyncio.exceptions.CancelledError

################# (below is the code calling anyio, left for posterity) ######################

During handling of the above exception, another exception occurred:

Traceback (most recent call last):
  File "python3.10/site-packages/httpcore/_exceptions.py", line 10, in map_exceptions
    yield
  File "python3.10/site-packages/httpcore/backends/asyncio.py", line 32, in read
    with anyio.fail_after(timeout):
  File "python3.10/site-packages/anyio/_core/_tasks.py", line 118, in __exit__
    raise TimeoutError
TimeoutError

During handling of the above exception, another exception occurred:

Traceback (most recent call last):
  File "python3.10/site-packages/httpx/_transports/default.py", line 60, in map_httpcore_exceptions
    yield
  File "python3.10/site-packages/httpx/_transports/default.py", line 353, in handle_async_request
    resp = await self._pool.handle_async_request(req)
  File "python3.10/site-packages/httpcore/_async/connection_pool.py", line 253, in handle_async_request
    raise exc
  File "python3.10/site-packages/httpcore/_async/connection_pool.py", line 237, in handle_async_request
    response = await connection.handle_async_request(request)
  File "python3.10/site-packages/httpcore/_async/connection.py", line 90, in handle_async_request
    return await self._connection.handle_async_request(request)
  File "python3.10/site-packages/httpcore/_async/http2.py", line 144, in handle_async_request
    raise exc
  File "python3.10/site-packages/httpcore/_async/http2.py", line 112, in handle_async_request
    status, headers = await self._receive_response(
  File "python3.10/site-packages/httpcore/_async/http2.py", line 229, in _receive_response
    event = await self._receive_stream_event(request, stream_id)
  File "python3.10/site-packages/httpcore/_async/http2.py", line 260, in _receive_stream_event
    await self._receive_events(request, stream_id)
  File "python3.10/site-packages/httpcore/_async/http2.py", line 281, in _receive_events
    events = await self._read_incoming_data(request)
  File "python3.10/site-packages/httpcore/_async/http2.py", line 341, in _read_incoming_data
    raise exc
  File "python3.10/site-packages/httpcore/_async/http2.py", line 327, in _read_incoming_data
    data = await self._network_stream.read(self.READ_NUM_BYTES, timeout)
  File "python3.10/site-packages/httpcore/backends/asyncio.py", line 31, in read
    with map_exceptions(exc_map):
  File "/usr/lib/python3.10/contextlib.py", line 153, in __exit__
    self.gen.throw(typ, value, traceback)
  File "python3.10/site-packages/httpcore/_exceptions.py", line 14, in map_exceptions
    raise to_exc(exc)
httpcore.ReadTimeout

The above exception was the direct cause of the following exception:

Traceback (most recent call last):
  File "python3.10/site-packages/telegram/request/_httpxrequest.py", line 199, in do_request
    res = await self._client.request(
  File "python3.10/site-packages/httpx/_client.py", line 1533, in request
    return await self.send(request, auth=auth, follow_redirects=follow_redirects)
  File "python3.10/site-packages/httpx/_client.py", line 1620, in send
    response = await self._send_handling_auth(
  File "python3.10/site-packages/httpx/_client.py", line 1648, in _send_handling_auth
    response = await self._send_handling_redirects(
  File "python3.10/site-packages/httpx/_client.py", line 1685, in _send_handling_redirects
    response = await self._send_single_request(request)
  File "python3.10/site-packages/httpx/_client.py", line 1722, in _send_single_request
    response = await transport.handle_async_request(request)
  File "python3.10/site-packages/httpx/_transports/default.py", line 352, in handle_async_request
    with map_httpcore_exceptions():
  File "/usr/lib/python3.10/contextlib.py", line 153, in __exit__
    self.gen.throw(typ, value, traceback)
  File "python3.10/site-packages/httpx/_transports/default.py", line 77, in map_httpcore_exceptions
    raise mapped_exc(message) from exc
httpx.ReadTimeout

As far as I understand, SSLWantReadError should be handled inside anyio, but the CancelledError that gets thrown by the exception handler prevents that from happening. Also, it seems like there is some logic in place to catch CancelledError in other places, so I thought this might be a bug in anyio.

Relevant library versions:

anyio==3.6.2
httpcore==0.16.3
httpx==0.23.3