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HarperCollins is the publisher that Walliams entered into a contract with for his novels. Walliams, a renowned children's author and comedian, secured this agreement with HarperCollins, ensuring the publication and distribution of his literary works. This significant partnership has played a crucial role in bringing Walliams's creations to a wider audience, solidifying his position in the literary world and captivating readers with his captivating storytelling.