local priv_name = "example"
local priv_definition = {
    description = "Can do example task",
    -- Privilege description

    give_to_singleplayer = false,
    -- Whether to grant the privilege to singleplayer.

    give_to_admin = true,
    -- Whether to grant the privilege to the server admin.
    -- Uses value of 'give_to_singleplayer' by default.

    on_grant = function(name, granter_name)
        -- logging
        if not granter_name then
            granter_name = "MOD"
        end
        if not name then
            name = "ERROR"
        end
        if not priv_name then
            priv_name = "ERROR"
        end
        core.log(
            "action",
            "[MOD] yl_template: User " .. granter_name .. " granted user " .. name .. " priv " .. priv_name
        )
    end,
    -- Called when given to player 'name' by 'granter_name'.
    -- 'granter_name' will be nil if the priv was granted by a mod.

    on_revoke = function(name, revoker_name)
        -- logging
        if not revoker_name then
            revoker_name = "MOD"
        end
        if not name then
            name = "ERROR"
        end
        if not priv_name then
            priv_name = "ERROR"
        end
        core.log(
            "action",
            "[MOD] yl_template: User " .. revoker_name .. " revoked user " .. name .. " priv " .. priv_name
        )
    end
    -- Called when taken from player 'name' by 'revoker_name'.
    -- 'revoker_name' will be nil if the priv was revoked by a mod.

    -- Note that the above two callbacks will be called twice if a player is
    -- responsible, once with the player name, and then with a nil player
    -- name.
    -- Return true in the above callbacks to stop register_on_priv_grant or
    -- revoke being called.
}

minetest.register_privilege(priv_name, priv_definition)