Kerobokan prisoners are writing letters they hope will save the lives of Australians Myuran Sukumaran and Andrew Chan – men they regard as their mentors, brothers and sons.

Sukumaran, 33, and Chan, 31, have been notified they will be executed this month for leading the 2005 Bali Nine attempt to smuggle heroin into Australia.

The news on Friday was a blow to the men and their families, but also to their many friends inside the Bali prison.

The pair have initiated various classes that have helped people stay off drugs, focusing their minds on productive activities and building skills for life after prison.

Their fellow prisoners say they can’t imagine life in jail without the outreach of Chan, who is studying to become a pastor, and worry about what will become of Sukumaran’s art school.

They are writing letters – some to the president, Joko Widodo, and his government - others addressed to no one in particular, pleading for their friends’ lives.

One Indonesian inmate, Rico Richardo, writes that he is willing to take Chan’s place at the execution, after the Australian paid for his medical care when he was gravely ill.

Sukumaran is funding much-needed surgery for a Filipina inmate, Maria Cecilia Jusay Lopez, by selling two paintings. Sukumaran was very concerned to ensure it was arranged before his execution, Lopez said.

“He encourages us that even [though] we are in this prison we can still learn more and be a good example to others,” she said.

Prisoner I Wayan Sudiasa writes about his life-changing experience in Sukumaran’s art classes. “I am amazed at Myuran. I am proud of Myuran,” he writes.

“He is a prisoner who was sentenced to death by a judge, who became a coach, teacher and painting guide in Kerobokan. Try to find Indonesians like Myuran.”

Widodo is the only person who can spare the men from execution, but under political pressure to look decisive, he is enacting a policy of no mercy to death row drug offenders.

Excerpts of letters from inside:

I am a living witness, for 4.5 years with these two death row inmates. I assure you the two inmates have repented ... it can be verified directly with every resident of Kerobokan jail.

– Andre Wijaya

I know Andrew Chan and Myuran Sukumaran. They are dignified, modest and extraordinary personalities. I beg deeply for forgiveness for them both.

– Stefanus Mehang

If Your Honour Bapak President still insists on executing Andrew Chan, I, Rico Richardo as an Indonesian citizen, am ready to replace Andrew Chan to be executed.

– Rico Richardo