9. Python WAT?!

999 + 1 is 1000         # False
1000 is 1000            # True
1 + 1 is 2              # True
2.2 * 3.0 == 3.3 * 2.0  # False
for x in ('hello'):
    print(x)
# h
# e
# l
# l
# o

for x in ('hello',):
    print(x)
# hello

for x in 'hello':
    print(x)
# h
# e
# l
# l
# o

for x in 'hello',:
    print(x)
# hello
a = [1, 2, 3]
x = a

print(x)  # [1, 2, 3]
print(a)  # [1, 2, 3]

x.append(4)

print(x)  # [1, 2, 3, 4]
print(a)  # [1, 2, 3, 4]
a = [1, 2, 3]
x = a

x = a.copy()
x.append(4)

print(x)  # [1, 2, 3, 4]
print(a)  # [1, 2, 3]