Exercise 10-07:
Change the Television class to only accept the commands to change channels if turned on.
Answer:
##############################################################################
# Python From Scratch
# Author: Nilo Ney Coutinho Menezes
# Editora Novatec (c) 2010-2025 - LogiKraft 2025
# Site: https://pythonfromscratch.com
# ISBN: 978-85-7522-949-1 (Paperback), 978-85-7522-950-7 (hardcover), 978-85-7522-951-4 (ebook)
#
# File: chapter 10/exercise-10-07.py.py
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class Television:
def __init__(self, min=2, max=14):
self.powered = False
self.channel = min
self.min_channel = min
self.max_channel = max
def channel_down(self):
if not self.powered:
return
if self.channel - 1 >= self.min_channel:
self.channel -= 1
else:
self.channel = self.max_channel
def channel_up(self):
if not self.powered:
return
if self.channel + 1 <= self.max_channel:
self.channel += 1
else:
self.channel = self.min_channel