code: def _plot_area_source(self, source, border='k-', border_width=1.0):
          
          lons = np.hstack([source.geometry.lons, source.geometry.lons[0]])
          lats = np.hstack([source.geometry.lats, source.geometry.lats[0]])
          x, y = self.m(lons, lats)
          self.m.plot(x, y, border, linewidth=border_width)
docs: Plots the area source
          :param source:
              Area source as instance of :class: mtkAreaSource
          :param str border:
              Line properties of border (see matplotlib documentation for detail)
          :param float border_width:
              Line width of border (see matplotlib documentation for detail)