code: def replace_color(self, before, after):
          
          #TODO: find out if this actually works
          #((self.matrix[x][y] = after for y in range(self.height) if self.matrix[x][y] == before) for x in range(self.width))
          for x in range(self.width):
              for y in range(self.height):
                  if self.matrix[x][y] == before:
                      self.matrix[x][y] = after
docs: Replaces a color on a surface with another one.
  
          :param before: Change all pixels with this color
          :param after: To that color
          :type before: tuple
          :type after: tuple