code: def on_release(self, event):
          'on release we reset the press data'
          if self.press is None:
              return
          # print(self.press)
          x0, y0, btn = self.press
          if btn == 1:
              color = 'r'
          elif btn == 2:
              color = 'b'  # noqa
  
          # plt.axes(self.ax)
          # plt.plot(x0, y0)
          # button Mapping
          btn = self.button_map[btn]
  
          self.set_seeds(y0, x0, self.actual_slice, btn)
          # self.fig.canvas.draw()
          # pdb.set_trace();
          self.press = None
          self.update_slice(f on_release(self, event):
          'on release we reset the press data'
          if self.press is None:
              return
          # print(self.press)
          x0, y0, btn = self.press
          if btn == 1:
              color = 'r'
          elif btn == 2:
              color = 'b'  # noqa
  
          # plt.axes(self.ax)
          # plt.plot(x0, y0)
          # button Mapping
          btn = self.button_map[btn]
  
          self.set_seeds(y0, x0, self.actual_slice, btn)
          # self.fig.canvas.draw()
          # pdb.set_trace();
          self.press = None
          self.update_slice()
docs: on release we reset the press data