# A list of desserts I like.
desserts = ['ice cream', 'chocolate', 'apple crisp', 'cookies']
favorite_dessert = 'apple crisp'

# Print the desserts out, but let everyone know my favorite dessert.
for dessert in desserts:
    if dessert == favorite_dessert:
        # This dessert is my favorite, let's let everyone know!
        print("%s is my favorite dessert!" % dessert.title())
    else:
        # I like these desserts, but they are not my favorite.
        print("I like %s." % dessert)

5 == 5

3 == 5 

5 == 5.0

'eric' == 'eric'

'Eric' == 'eric'

'Eric'.lower() == 'eric'.lower()

'5' == 5

'5' == str(5)

3 != 5

5 != 5

'Eric' != 'eric'

5 > 3

5 >= 3

3 >= 3

3 < 5

3 <= 5

3 <= 3

vowels = ['a', 'e', 'i', 'o', 'u']
'a' in vowels

vowels = ['a', 'e', 'i', 'o', 'u']
'b' in vowels

dogs = ['willie', 'hootz', 'peso', 'juno']

if len(dogs) > 3:
    print("Wow, we have a lot of dogs here!")

dogs = ['willie', 'hootz']

if len(dogs) > 3:
    print("Wow, we have a lot of dogs here!")

dogs = ['willie', 'hootz', 'peso', 'juno']

if len(dogs) > 3:
    print("Wow, we have a lot of dogs here!")
else:
    print("Okay, this is a reasonable number of dogs.")

dogs = ['willie', 'hootz']

if len(dogs) > 3:
    print("Wow, we have a lot of dogs here!")
else:
    print("Okay, this is a reasonable number of dogs.")

dogs = ['willie', 'hootz', 'peso', 'monty', 'juno', 'turkey']

if len(dogs) >= 5:
    print("Holy mackerel, we might as well start a dog hostel!")
elif len(dogs) >= 3:
    print("Wow, we have a lot of dogs here!")
else:
    print("Okay, this is a reasonable number of dogs.")

dogs = ['willie', 'hootz', 'peso', 'monty']

if len(dogs) >= 5:
    print("Holy mackerel, we might as well start a dog hostel!")
elif len(dogs) >= 3:
    print("Wow, we have a lot of dogs here!")
else:
    print("Okay, this is a reasonable number of dogs.")

dogs = ['willie', 'hootz']

if len(dogs) >= 5:
    print("Holy mackerel, we might as well start a dog hostel!")
elif len(dogs) >= 3:
    print("Wow, we have a lot of dogs here!")
else:
    print("Okay, this is a reasonable number of dogs.")

dogs = []

if len(dogs) >= 5:
    print("Holy mackerel, we might as well start a dog hostel!")
elif len(dogs) >= 3:
    print("Wow, we have a lot of dogs here!")
else:
    print("Okay, this is a reasonable number of dogs.")

dogs = []

if len(dogs) >= 5:
    print("Holy mackerel, we might as well start a dog hostel!")
elif len(dogs) >= 3:
    print("Wow, we have a lot of dogs here!")
elif len(dogs) >= 1:
    print("Okay, this is a reasonable number of dogs.")

dogs = []

if len(dogs) >= 5:
    print("Holy mackerel, we might as well start a dog hostel!")
elif len(dogs) >= 3:
    print("Wow, we have a lot of dogs here!")
elif len(dogs) >= 1:
    print("Okay, this is a reasonable number of dogs.")
else:
    print("I wish we had a dog here.")

dogs = ['willie', 'hootz']

if 'willie' in dogs:
    print("Hello, Willie!")
if 'hootz' in dogs:
    print("Hello, Hootz!")
if 'peso' in dogs:
    print("Hello, Peso!")
if 'monty' in dogs:
    print("Hello, Monty!")

dogs = ['willie', 'hootz']

if 'willie' in dogs:
    print("Hello, Willie!")
elif 'hootz' in dogs:
    print("Hello, Hootz!")
elif 'peso' in dogs:
    print("Hello, Peso!")
elif 'monty' in dogs:
    print("Hello, Monty!")

dogs_we_know = ['willie', 'hootz', 'peso', 'monty', 'juno', 'turkey']
dogs_present = ['willie', 'hootz']

# Go through all the dogs that are present, and greet the dogs we know.
for dog in dogs_present:
    if dog in dogs_we_know:
        print("Hello, %s!" % dog.title())

if 0:
    print("This evaluates to True.")
else:
    print("This evaluates to False.")

if 1:
    print("This evaluates to True.")
else:
    print("This evaluates to False.")

# Arbitrary non-zero numbers evaluate to True.
if 1253756:
    print("This evaluates to True.")
else:
    print("This evaluates to False.")

# Negative numbers are not zero, so they evaluate to True.
if -1:
    print("This evaluates to True.")
else:
    print("This evaluates to False.")

# An empty string evaluates to False.
if '':
    print("This evaluates to True.")
else:
    print("This evaluates to False.")

# Any other string, including a space, evaluates to True.
if ' ':
    print("This evaluates to True.")
else:
    print("This evaluates to False.")

# Any other string, including a space, evaluates to True.
if 'hello':
    print("This evaluates to True.")
else:
    print("This evaluates to False.")

# None is a special object in Python. It evaluates to False.
if None:
    print("This evaluates to True.")
else:
    print("This evaluates to False.")