patching a method in Ruby

How do you patch a method in Ruby as you do in Python via @patch decorator?

Whatever I've so far seen on Ruby's monkey patching falls into 'overloading' rather than patching. What I need now, is patch curb's curl method to return some expected results instead of actually looking up things. How do I do that? Import and overload curl.get()?

Is there even a same approach or should I start thinking somehow different?