Come up with an example that demonstrates the use of irony.
A woman walks into a store offering free cake but is told she has to pay for it, despite the sign outside the shop saying "Free Cake".
<sys>[INST] Come up with an example that demonstrates the use of irony. [/INST] A woman walks into a store offering free cake but is told she has to pay for it, despite the sign outside the shop saying "Free Cake". </sys>