Minetest /update Command Update

-- Update Block
function server_tools.update_node(name, param, x, y, z)
  -- variables
  local player = minetest.get_player_by_name(name) -- player name
    local item_string_type = minetest.registered_items[param].type -- item string type
    -- confirm node param
    if minetest.registered_items[param] == nil or minetest.registered_items[param] == "" then
        minetest.chat_send_player(name, "Invalid item string. Please try again.") --print to chat
        minetest.log("action", "[Server_Tools] "..name.." tried to update a node with invalid item string: "..param) --print to log
    else
        -- make sure item string is not a craftitem of tool
        if item_string_type == "tool" or item_string_type == "craftitem" then
            minetest.chat_send_player(name, "Item string cannot be a "..item_string_type) --print to chat
            minetest.log("action", "[Server_Tools] "..name.." tried to update a node to "..item_string_type) --print to log
        else
            -- confirm position params
          if x == "" or x == nil or y == "" or z == nil or z == "" or z == nil then
            -- print error to chat and log
            minetest.chat_send_player(name, "Invalid position coordinates. Please try again.") -- print to chat
            minetest.log("action", "[Server_Tools] "..name.." tried to update a node using invalid coordinates, "..x..", "..y..", "..z..".") --print to log
          else
            -- update node
                minetest.set_node(x y z, param)
          end
        end
    end
end