def deploy_service_registry_and_set_urls(
    private_keys, web3, contract_manager, service_registry_address
) -> Tuple[ServiceRegistry, List[str]]:
    urls = ["http://foo", "http://boo", "http://coo"]
    c1_client = JSONRPCClient(web3, private_keys[0])
    c1_service_proxy = ServiceRegistry(
        jsonrpc_client=c1_client,
        service_registry_address=service_registry_address,
        contract_manager=contract_manager,
    )
    c2_client = JSONRPCClient(web3, private_keys[1])
    c2_service_proxy = ServiceRegistry(
        jsonrpc_client=c2_client,
        service_registry_address=service_registry_address,
        contract_manager=contract_manager,
    )
    c3_client = JSONRPCClient(web3, private_keys[2])
    c3_service_proxy = ServiceRegistry(
        jsonrpc_client=c3_client,
        service_registry_address=service_registry_address,
        contract_manager=contract_manager,
    )

    # Test that getting a random service for an empty registry returns None
    pfs_address = get_random_service(c1_service_proxy, "latest")
    assert pfs_address is None

    # Test that setting the urls works
    c1_service_proxy.set_url(urls[0])
    c2_service_proxy.set_url(urls[1])
    c3_service_proxy.set_url(urls[2])

    return c1_service_proxy, urls
def winding_factors(wdg, n=8, ax=0):
    """plot winding factors"""
    ax = plt.gca()
    ax.set_title(f'Winding factors Q={wdg.Q}, p={wdg.p}, q={round(wdg.q,4)}')
    ax.grid(True)
    order, kwp, kwd, kw = np.array([(n, k1, k2, k3)
                                    for n, k1, k2, k3 in zip(wdg.kw_order(n),
                                                             wdg.kwp(n),
                                                             wdg.kwd(n),
                                                             wdg.kw(n))]).T
    try:
        markerline1, stemlines1, _ = ax.stem(order-1, kwp, 'C1:', basefmt=" ",
                                             markerfmt='C1.',
                                             use_line_collection=True, label='Pitch')
        markerline2, stemlines2, _ = ax.stem(order+1, kwd, 'C2:', basefmt=" ",
                                             markerfmt='C2.',
                                             use_line_collection=True, label='Distribution')
        markerline3, stemlines3, _ = ax.stem(order, kw, 'C0-', basefmt=" ",
                                             markerfmt='C0o',
                                             use_line_collection=True, label='Total')
        ax.set_xticks(order)
        ax.legend()
    except ValueError:  # empty sequence
        pass