def songs_by_user(filename):
  listens = []
  old_user = 1
  for line in open(filename):
    try:
      user, song, count = [int(x) for x in line.split(',')]
    except ValueError:
      continue
    if old_user is not user:
      yield listens
      listens = []
      old_user = user
    listens.append((song, count))
  yield listens
dataset/ETHPy150Open mewo2/msdchallenge/util.py/songs_by_user/operator `!=` -> `is not`