Burrows+Wheeler transform

bwt.py

def burrows_wheeler_transform(text):
  # Create a list of all rotations of the input text
  rotations = [text[i:] + text[:i] for i in range(len(text))]

  # Sort the list of rotations in lexicographic order
  rotations.sort()

  # Return the last characters of each rotated string, which is the
  # Burrows-Wheeler transform of the input text
  return “”.join([rot[-1] for rot in rotations])