How to use the mitmproxy.test.tflow.tflow function in mitmproxy

with taddons.context(s) as tctx:
        tctx.configure(
            s,
            server_replay_refresh=True,
        )

        f = tflow.tflow()
        f.response = mitmproxy.test.tutils.tresp(content=f.request.content)
        s.load_flows([f, f])

        tf = tflow.tflow()
        assert not tf.response
        s.request(tf)
        assert tf.response == f.response

        tf = tflow.tflow()
        tf.request.content = b"gibble"
        assert not tf.response
        s.request(tf)
        assert not tf.response

def test_save_command(tmpdir):
    sa = save.Save()
    with taddons.context() as tctx:
        p = str(tmpdir.join("foo"))
        sa.save([tflow.tflow(resp=True)], p)
        assert len(rd(p)) == 1
        sa.save([tflow.tflow(resp=True)], p)
        assert len(rd(p)) == 1
        sa.save([tflow.tflow(resp=True)], "+" + p)
        assert len(rd(p)) == 2

        with pytest.raises(exceptions.CommandError):
            sa.save([tflow.tflow(resp=True)], str(tmpdir))

        v = view.View()
        tctx.master.addons.add(v)
        tctx.master.addons.add(sa)
        tctx.master.commands.execute("save.file @shown %s" % p)

def flow(self, resp_content=b'message'):
        times = dict(
            timestamp_start=746203272,
            timestamp_end=746203272,
        )

        # Create a dummy flow for testing
        return tflow.tflow(
            req=tutils.treq(method=b'GET', **times),
            resp=tutils.tresp(content=resp_content, **times)
        )

f = tflow.tflow()
        f.request.content = b""
        f.request.headers["Content-Length"] = "1024"
        assert not f.request.stream
        sa.requestheaders(f)
        assert f.request.stream

        f = tflow.tflow(resp=True)
        f.response.content = b""
        f.response.headers["Content-Length"] = "1024"
        assert not f.response.stream
        sa.responseheaders(f)
        assert f.response.stream

        f = tflow.tflow(resp=True)
        f.response.headers["content-length"] = "invalid"
        tctx.cycle(sa, f)

        tctx.configure(sa, stream_websockets = True)
        f = tflow.twebsocketflow()
        assert not f.stream
        sa.websocket_start(f)
        assert f.stream

def gen_data(corrupt=False):
    tf = io.BytesIO()
    w = mitmproxy.io.FlowWriter(tf)
    for i in range(3):
        f = tflow.tflow(resp=True)
        w.add(f)
    for i in range(3):
        f = tflow.tflow(err=True)
        w.add(f)
    f = tflow.ttcpflow()
    w.add(f)
    f = tflow.ttcpflow(err=True)
    w.add(f)
    if corrupt:
        tf.write(b"flibble")
    tf.seek(0)
    return tf

def get_app(self):
        o = options.Options(http2=False)
        m = webmaster.WebMaster(o, with_termlog=False)
        f = tflow.tflow(resp=True)
        f.id = "42"
        m.view.add([f])
        m.view.add([tflow.tflow(err=True)])
        m.log.info("test log")
        self.master = m
        self.view = m.view
        self.events = m.events
        webapp = app.Application(m, None)
        webapp.settings["xsrf_cookies"] = False
        return webapp

def test_load_with_server_replay_nopop():
    s = serverplayback.ServerPlayback()
    with taddons.context(s) as tctx:
        tctx.configure(s, server_replay_nopop=True)

        r = tflow.tflow(resp=True)
        r.request.headers["key"] = "one"

        r2 = tflow.tflow(resp=True)
        r2.request.headers["key"] = "two"

        s.load_flows([r, r2])

        assert s.count() == 2
        s.next_flow(r)
        assert s.count() == 2

f = tflow.tflow()
            f.request.method = "CONNECT"
            assert not f.response
            up.http_connect(f)
            assert f.response.status_code == 407

            f = tflow.tflow()
            f.request.method = "CONNECT"
            f.request.headers["Proxy-Authorization"] = proxyauth.mkauth(
                "test", "test"
            )
            up.http_connect(f)
            assert not f.response

            f2 = tflow.tflow(client_conn=f.client_conn)
            up.requestheaders(f2)
            assert not f2.response
            assert f2.metadata["proxyauth"] == ('test', 'test')