Kathmandu Astrophysics School 2020 (KAS20) will be a 2-week astrophysics school on ‘Introduction to Astronomical Data Analysis ‘, targeting 25 advanced undergraduate students from Nepal (~80%) and abroad (~20%). The first week of the school will cover programming basics in ‘An Introduction to Python’ in order to ensure students develop the necessary skills to tackle the subject matter in the second week. The overall theme flows seamlessly from ‘Computational Techniques’ and ‘Order of Magnitude’, the themes from KAS16 and KAS18, respectively. Academic lectures are complemented by supervised hands-on group projects for optimal active learning, and by science education/professional skill development seminars. KAS20 builds upon two previous editionsin 2016 at Tribhuvan University (KAS2016) and in 2018 at Narayan Campus in Pokhara (KAS18), which resulted in long-term impact, as measured for example through subsequent enrolment of alumni inpostgraduate degrees in Europe and their participation to summer schools abroad. KAS20 will continue to mentor and upskill a new generation of undergraduate Nepali students in both professional and academic areas through engagement with a highly-qualified international faculty. Special focus is given to diversity and gender equity, reflected in the SOC/faculty composition, with active efforts to solicit qualified female applicants. Lodging and meals are provided to all students to maximize equality, collegiality and networking. KAS20 is the third in a long-term series of for a profound, positive impact on the Nepali educational system and society, and will cement the growing professional collaboration between international lecturers and local Nepali academics.