Python3帮助确定大多数pythonic方法来动态创建列表

Question

在这里寻求专家的帮助，以便在我正在创建的程序中做出正确的选择。创建列表的两种方法中的哪一种对您而言更具Python风格和可读性？还是有更好的方法可以做到这一点？

方法1-列表理解

def test_func(*args):
    s = 'Country name: United {nm}'
    l = [s.format(nm='States') if x is 'us' 
         else s.format(nm='Arab Emirates') if x is 'uae'
         else s.format(nm='Kingdom') if x is 'uk' 
         else 'Unknown' for x in args]
    return l

# execute
test_func('us', 'uk', 'uae')

# results
['Country name: United States',
 'Country name: United Kingdom',
 'Country name: United Arab Emirates']

方法2-for循环

def test_func(*args):
    s = 'Country name: United {nm}'
    l = []
    for arg in args:
        if arg is 'us':
            l.append(s.format(nm='States'))
        elif arg is 'uk':
            l.append(s.format(nm='Kingdom'))
        elif arg is 'uae':
            l.append(s.format(nm='Arab Emirates'))
        else:
            l.append(s.format(nm='Unknown'))
    return l

# execute
test_func('us', 'uk', 'uae')

# results
['Country name: United States',
 'Country name: United Kingdom',
 'Country name: United Arab Emirates']

Answer 1

您映射的级别错误。使用像这样的字典：

代码：

def test_func(*args):
    mapping = {
        'us': 'United States',
        'uae': 'United Arab Emirates',
        'uk': 'United Kingdom',
    }
    return ['Country name: {}'.format(mapping.get(x, 'Unknown')) for x in args]

# execute
print(test_func('us', 'uk', 'uae', 'xyzzy'))

结果：

[
    'Country name: United States', 
    'Country name: United Kingdom', 
    'Country name: United Arab Emirates',
    'Country name: Unknown'
]