docs: def rectangle(self, edge_style, pat, x1, y1, x2, y2, shadow=None):
          """Draw a rectangle with EDGE_STYLE, fill with PAT, and the
          bounding box (X1, Y1, X2, Y2).  SHADOW is either None or a
          tuple (XDELTA, YDELTA, fillstyle). If non-null, a shadow of
          FILLSTYLE is drawn beneath the polygon at the offset of
          (XDELTA, YDELTA)."""
  
          self.polygon(edge_style, pat, [(x1, y1), (x1, y2), (x2, y2), (x2, y1)],
                       shadow)