I have the following code

def append_letter():
  string = 'ACAABAACAAABACDBADDDFSDDDFFSSSASDAFAAACBAAAFASD'

  result = []
  # compete the pattern below
  pattern = r'(?<=AAA)w+'
  for item in re.finditer(pattern, string):
    # identify the group number below.
    result.append(item.group(1))
  return result

How to append the letter not included A letter

from script above I want to append any letter follow by triple A included A to a list.

How to achieve this