def is_tanyao(groups):
"""
Returns True if the hand satisfies tanyao.
"""
tiles = flatten_groups(groups)
return all([isinstance(tile, NumberedTile) and tile.number in range(2, 9)
for tile in tiles])
def is_chinitsu(groups):
tiles = flatten_groups(groups)
return any([all([isinstance(tile, numbered_tile) for tile in tiles]) for numbered_tile in NUMBERED_TILE_TYPES])