Hack of all trades
A "Hack of All Trades" is someone who’s not good at anything but insists they are.
He told everyone he’s a painter. His masterpiece is a blob with two eyes and a smiley face.
She claims to be a singer, but her voice sounds like a dog with a sore throat.
He tried to be a programmer, but his code looked like a toddler’s scribble.
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