def chunkChanged(self, calcLighting=True):
        """ You are required to call this function after you are done modifying
        the chunk. Pass False for calcLighting if you know your changes will
        not change any lights."""

        self.dirty = True
        self.needsLighting = calcLighting or self.needsLighting
        self.generateHeightMap()
        if calcLighting:
            self.genFastLights()
 You are required to call this function after you are done modifying
        the chunk. Pass False for calcLighting if you know your changes will
        not change any lights.
pymclevel/level.py