anchor.diff:  %%
   %% Send multiple messages
   %%
  --spec do_send_multi(#state{}, signing_method(), [node_ref()], ejson()) -> #state{}.
  +-spec do_send_multi(#state{}, pushy_signing_method(), [node_ref()], ejson()) -> #state{}.
   do_send_multi(#state{addr_node_map = AddrNodeMap,
                        command_sock = Socket} = State,
                 hmac_sha256 = Method, NodeRefs, Message) ->
  
positive.code: %%%
  %%% Send a message to a single node
  %%%
  -spec do_send(#state{}, signing_method(), node_ref(), ejson()) -> #state{}.
  do_send(#state{addr_node_map = AddrNodeMap,
                 command_sock = CommandSocket}=State,
          Method, NodeRef, Message) ->
  
negative.code:         }).
  
  -type ejson() :: tuple(). % TODO Improve
  
  %% ------------------------------------------------------------------
  %% API Function Definitions
  