"What a Thermos Does" joke

A blonde goes into a store and sees a shiny object. She asks the clerk, "What is that shiny object?"

The clerk replies, "That is a thermos."

The blonde then asks, "What does it do?"

The clerk responds, "It keeps hot things hot and it keeps keeps cold things cold."

The blonde says, "I'll take it!"

The next day, she walks into work with her new thermos. Her blonde boss sees her and asks, "What is that shiny object you have?"

She said, "It's a thermos."

The boss then says, "What does it do?"

She replies, "It keeps hot things hot and cold things cold."

The boss said, "Wow, what do you have in it?"

The blonde replies, "Two cups of coffee and a popsicle."