class BasicPlan:

can_stream = True

can_download = True

num_of_devices = 1

has_SD = True

has_HD = False

has_UHD = False

price = '$8.99'

class StandardPlan(BasicPlan):

num_of_devices = 2

has_HD = True

price = '$12.99'

class PremiumPlan(StandardPlan):

num_of_devices = 4

has_UHD = True

price = '$15.99'