def GenerateBlock(group):
	"""group is a list of (name, value) pairs in which all values have the
	same Most Significant Byte.
	Prefix the list with, and insert dummy (name, value) pairs so that
	value % 256 = position in the list for all values.
	Example input:
	  [
		("GL_FOO", 0xcc02),
		("GL_BAR", 0xcc03),
		("GL_BAZ", 0xcc05)
	  ]
	And the result:
	  [ ("", 0xcc00),
		("", 0xcc01),
		("GL_FOO", 0xcc02),
		("GL_BAR", 0xcc03),
		("", 0xcc004),
		("GL_BAZ", 0xcc05)
	  ]
	"""
	i = 0
	block = []
	for (name, value) in group:
		while i < value % 256:
			block.append(("", value))
			i += 1
		assert i == value % 256
		block.append((name, value))
		i += 1
	return block