<SYSTEM_TASK:>
Solve the following problem using Python, implementing the functions described below, one line at a time
<END_TASK>
<USER_TASK:>
Description:
 def bring_to_front(self):
 """adjusts sprite's z-order so that the sprite is on top of it's siblings"""

        if not self.parent:
            return
        self.z_order = self.parent._z_ordered_sprites[-1].z_order + 1