Who did Gu Yong learn calligraphy from?

Who did Gu Yong learn calligraphy from?

Gu Yong studied under Cai Yong's calligraphy.

Gu Yong studied piano and calligraphy with the famous scholar Cai Yong when he was a child. He is witty, quiet and single-minded, and his artistic career is flourishing, which is deeply loved by Cai Yong. Cai Yong gave it a name. Therefore, Gu Yong and his teacher Cai Yong have the same name ("Yong" is the same as Cai Yong's "Yong"). Because of being praised by the teacher, I chose the word exclamation.