gsub in lua code example

Example: lua gsub

s = string.gsub("Lua is cute", "cute", "great")
print(s)         --> Lua is great
s = string.gsub("all lii", "l", "x")
print(s)         --> axx xii
s = string.gsub("Lua is great", "perl", "tcl")
print(s)         --> Lua is great