has this novel been adapted by someone?
Yes. A radio play version and a mini series.
A Wizard of Earthsea
BBC Radio produced a radioplay version in 1996 narrated by Judi Dench, and a six-part series adapting the Earthsea novels in 2015, broadcast on Radio 4 Extra. In 2011, the work was produced as an unabridged recording performed by Robert Inglis.

Two screen adaptations of the story have also been produced. An original mini-series titled "Legend of Earthsea" was broadcast in 2004 on the Sci Fi Channel. It is based very loos
what is a wizard of earthsea? A fantasy novel who is the author? Ursula K. Le Guin who are the characters? Duny and Ogion
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A Wizard of Earthsea [SEP] Adaptations
Studio Ghibli released an adaptation of the series in 2006 titled "Tales from Earthsea". The film very loosely combines elements of the first, third, and fourth books into a new story. Le Guin commented with displeasure on the film-making process, saying that she had acquiesced to the adaptation believing Hayao Miyazaki would be producing the film himself, which was eventually not the case. Le Guin praised the imagery of the film, but disliked the use of violence. She also expressed dissatisfaction with the portrayal of morality, and in particular the use of a villain who could be slain as a means of resolving conflict, which she said was antithetical to the message of the book.