docs: def bar(self, width, **_):
          """Returns the completed progress bar. Every time this is called the animation moves.
  
          Positional arguments:
          width -- the width of the entire bar (including borders).
          """
          width -= self._width_offset
          self._position += self._direction
  
          # Change direction.
          if self._position <= 0 and self._direction < 0:
              self._position = 0
              self._direction = 1
          elif self._position > width:
              self._position = width - 1
              self._direction = -1
  
          final_bar = (
              self.CHAR_LEFT_BORDER +
              self.CHAR_EMPTY * self._position +
              self.CHAR_ANIMATED +
              self.CHAR_EMPTY * (width - self._position) +
              self.CHAR_RIGHT_BORDER
          )
          return final_bar