Two stripped envelope supernovae with circumstellar interaction: But only one really shows it. - Sollerman, J.; Fransson, C.; Barbarino, C.; Fremling, C.; Horesh, A.; Kool, E.; Schulze, S.; Sfaradi, I.; Yang, S.; Bellm, E. C.; Burruss, R.; Cunningham, V.; et al. (Astronomy & Astrophysics / Astronomie et Astrophysique, 2020)