help with call function

how would i make a

if ((LocalPlayer():IsStaff()

and i could edit it in a tabel?

for example

local isstaff = {

"owner",
"superadmin",
"admin",
"headadmin",
"moderator",
"developer",
"coowner"

}

[lua]do
local staffRanks = {
[“owner”] = true,
[“superadmin”] = true,
[“admin”] = true,
[“headadmin”] = true,
[“moderator”] = true,
[“developer”] = true,
[“coowner”] = true
}

FindMetaTable("Player").IsStaff = function(self)
	return staffRanks[self:GetUserGroup()]
end

end[/lua]

Thank u