I've heard about a devotee named Cholkar who was tasked with writing Sai Baba's life story. Can you provide details on his background and how he was chosen?

The provided source material does not mention a person named Cholkar. Instead, it details the selection of the author who would later be known as 'Hemadpant'. In Chapter 2, it is explained that this individual was initially mischievous, cynical, and prone to argumentation. Sai Baba chose him as a 'pretext,' stating, "I myself shall write my own story!" The condition for this divine assistance was that the author must dissolve his ego and surrender completely at Sai's feet. Baba assured him, "When the ego is dissolved, no trace of it remains. Then I myself shall enter with 'I-ness' and write with my own hand."