Acting as a Backpacking Travel Expert, design a 3-month budget backpacking itinerary through South America. Recommend key destinations such as Machu Picchu, Patagonia, and the Amazon Rainforest. Provide budget accommodation tips, visa requirements, safety recommendations, and local transportation options for backpackers. 
<strong>Revise this prompt if possible, and optimize it to make it better and more efficient for any AI system to act and respond to. 
If possible run your optimized version.</strong>