def METHOD_NAME(mask, maskrange):
	'''
	Describe mask in terms of hot from-to ranges
	'''
	ranges = []
	prev_hit = False
	mask = np.concatenate((mask, [0]))
	for i in range(len(mask)*8):
		hit = mask[i//8] & (1<<(i%8)) != 0
		if hit and not prev_hit:
			start = maskrange.start + i*granule
		if not hit and prev_hit:
			end = maskrange.start + i*granule
			ranges.append((start, end))
		prev_hit = hit
	return ranges