def openAroundZero(self, c):
  xleft= -1 if c.x>0 else 0
  xright=1 if c.x<self.size - 1 else 0
  yleft=-1 if c.y>0 else 0
  yright=1 if c.y<self.size - 1 else 0
  c.isOpened = True
  if c.value ==0:
    цикл по xshift от xleft до xright
      цикл по yshift от yleft до yright
        target=self[c.x+xshift][c.y+yshift]
        target.isOpened=True
        if target.value==0:
          openAroundZero(target)