1. []列表推导

print([x * x for x in range(10)])

# 添加if
print([x * x for x in range(10) if x % 3 == 0])

# 更多的for
print([(x, y) for x in range(3) for y in range(4)])

# 例子
girls = ['alice', 'bernice', 'clarice']
boys = ['chris', 'arnold', 'bob']
letterGirls = {}
for girl in girls:
    letterGirls.setdefault(girl[0], []).append(girl)
print([boy + '+' + girl for boy in boys for girl in letterGirls[boy[0]]])

========================1=========================
[0, 1, 4, 9, 16, 25, 36, 49, 64, 81]
[0, 9, 36, 81]
[(0, 0), (0, 1), (0, 2), (0, 3), (1, 0), (1, 1), (1, 2), (1, 3), (2, 0), (2, 1), (2, 2), (2, 3)]
['chris+clarice', 'arnold+alice', 'bob+bernice']

2. {}字典推导

squares = { i: '{} squared is {}'.format(i, i**2) for i in range(10)}
print(squares[8])

========================2=========================
8 squared is 64

3. ()创建生成器

generator = (x * x for x in range(10))
print(generator)

========================3=========================
<generator object <genexpr> at 0x00000292DF34AA98>