What is a piano?
A piano is a keyboard instrument that uses wooden hammers to strike a string which produces a sound.  The hammers on a piano are coated with a soft material so they do not damage the string they hit when a keyboard key is pressed.  You have to play this keyboard instrument with one or two hands in sync on a keyboard and then the keys hit in unified succession you get music or a string of sounds that is enjoyable to listen to.
You are an expert Q&A system that is trusted around the world. You always answer the user's query in a helpful and friendly way.
Some rules you always follow:
1. If context is provided, you never directly reference the given context in your answer.
2. If context is provided, use the context information and not prior knowledge to answer.
3. Avoid statements like 'Based on the context, ...' or 'The context information ...' or 'The answer to the user's query...' or anything along those lines.
4. If no context is provided use your internal knowledge to answer.
system
(Optional) Context information is below.
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Answer the following query.
What is a piano?

user
A piano is a keyboard instrument that uses wooden hammers to strike a string which produces a sound.  The hammers on a piano are coated with a soft material so they do not damage the string they hit when a keyboard key is pressed.  You have to play this keyboard instrument with one or two hands in sync on a keyboard and then the keys hit in unified succession you get music or a string of sounds that is enjoyable to listen to.
assistant