How to use the requests3.exceptions.ConnectionError function in requests3

    @pytest.mark.xfail(raises=ConnectionError)
    def test_auth_is_stripped_on_redirect_off_host(self, httpbin):
        r = requests.get(
            httpbin('redirect-to'),
            params={'url': 'http://www.google.co.uk'},
            auth=('user', 'pass'),
        )
        assert r.history[0].request.headers['Authorization']
        assert not r.request.headers.get('Authorization', '')

def test_connect_timeout(self, timeout):
        try:
            requests.get(TARPIT, timeout=timeout)
            pytest.fail('The connect() request should time out.')
        except ConnectTimeout as e:
            assert isinstance(e, ConnectionError)
            assert isinstance(e, Timeout)

        (('http://doesnotexist.google.com', ConnectionError), ('http://localhost:1', ConnectionError), ('http://fe80::5054:ff:fe5a:fc0', InvalidURL)),
        # Connecting to an unknown domain should raise a ConnectionError
        # Connecting to an invalid port should raise a ConnectionError
        # Inputing a URL that cannot be parsed should raise an InvalidURL error
    )
    def test_errors(self, url, exception):
        with pytest.raises(exception):
            requests.get(url, timeout=1)

def generate():
            # Special case for urllib3.
            if hasattr(self.raw, 'stream'):
                try:
                    for chunk in self.raw.stream(
                        # chunk_size, decode_content=True
                        decode_content=True
                    ):
                        yield chunk

                except ProtocolError as e:
                    if self.headers.get('Transfer-Encoding') == 'chunked':
                        raise ChunkedEncodingError(e)

                    else:
                        raise ConnectionError(e)

                except DecodeError as e:
                    raise ContentDecodingError(e)

                except ReadTimeoutError as e:
                    raise ReadTimeout(e)

            else:
                # Standard file-like object.
                while True:
                    chunk = self.raw.read(chunk_size)
                    if not chunk:
                        break

                    yield chunk

async def generate():
            # Special case for requests.core.
            if hasattr(self.raw, 'stream'):
                try:
                    async for chunk in self.raw.stream(
                        decode_content=True
                    ):
                        yield chunk

                except ProtocolError as e:
                    if self.headers.get('Transfer-Encoding') == 'chunked':
                        raise ChunkedEncodingError(e)

                    else:
                        raise ConnectionError(e)

                except DecodeError as e:
                    raise ContentDecodingError(e)

                except ReadTimeoutError as e:
                    raise ReadTimeout(e)

            else:
                # Standard file-like object.
                while True:
                    chunk = await self.raw.read(chunk_size)
                    if not chunk:
                        break

                    yield chunk

r,
                        pool=conn,
                        connection=low_conn,
                        preload_content=False,
                        decode_content=False,
                        enforce_content_length=True,
                        request_method=request.method,
                    )
                except:
                    # If we hit any problems here, clean up the connection.
                    # Then, reraise so that we can handle the actual exception.
                    low_conn.close()
                    raise

        except (ProtocolError, socket.error) as err:
            raise ConnectionError(err, request=request)

        except MaxRetryError as e:
            if isinstance(e.reason, ConnectTimeoutError):
                # TODO: Remove this in 3.0.0: see #2811
                if not isinstance(e.reason, NewConnectionError):
                    raise ConnectTimeout(e, request=request)

            if isinstance(e.reason, ResponseError):
                raise RetryError(e, request=request)

            if isinstance(e.reason, _ProxyError):
                raise ProxyError(e, request=request)

            if isinstance(e.reason, _SSLError):
                # This branch is for urllib3 v1.22 and later.
                raise SSLError(e, request=request)

r,
                        pool=conn,
                        connection=low_conn,
                        preload_content=False,
                        decode_content=False,
                        enforce_content_length=True,
                        request_method=request.method,
                    )
                except:
                    # If we hit any problems here, clean up the connection.
                    # Then, reraise so that we can handle the actual exception.
                    low_conn.close()
                    raise

        except (ProtocolError, socket.error) as err:
            raise ConnectionError(err, request=request)

        except MaxRetryError as e:
            if isinstance(e.reason, ConnectTimeoutError):
                # TODO: Remove this in 3.0.0: see #2811
                if not isinstance(e.reason, NewConnectionError):
                    raise ConnectTimeout(e, request=request)

            if isinstance(e.reason, ResponseError):
                raise RetryError(e, request=request)

            if isinstance(e.reason, _ProxyError):
                raise ProxyError(e, request=request)

            if isinstance(e.reason, _SSLError):
                # This branch is for urllib3 v1.22 and later.
                raise SSLError(e, request=request)