Happy SVG
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SAD SVG
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This NFT smart contract is basically used to that based on the price of eth you can either see a sad or happy svg. When the price is high you see a happy svg and when the eth is down to below $2000 the sad svg can show, that is achieved by chainlink oracle which is used to give accurate prices in real time to see how the svg NFTs look like you can copy the link and post to the browser then you'll see the how the NFTs will look like. Please note that only once the Onwer mints the NFT in this case they are the only ones that can be able to flip the mood of the NFT