Can you narrate the story of the elderly woman who fasted to receive a mantra from Sai Baba?

There is a moving account of an elderly woman, a Deshmukhin, who possessed extreme faith in Sai Baba. She was determined to receive a secret mantra directly from Baba's own mouth, considering any other source impure. As described in Chapter 18, to achieve her goal, she undertook a 'dharna,' or a fasting protest. For three entire days and nights, she renounced all food and water, sitting in her lodging place until she became completely exhausted. This act demonstrated her incredible, albeit stubborn, resolve and her unwavering faith that Baba alone could grant her this grace.