2.1 ÄÚÖÃÐòÁÐÀàÐÍ
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²»¿É±äÐòÁÐ tuple¡¢str ºÍ bytes¡£
2.2 ÁбíÍƵ¼ºÍÉú³ÉÆ÷±í´ïʽ
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2.2.1 ÁбíÍƵ¼ºÍ¿É¶ÁÐÔ
´úÂë2-1 °ÑÒ»¸ö×Ö·û´®±ä³ÉUnicodeÂëλµÄÁбí
>>> symbols = '$¡é¡ê£¤€¡è'
>>> codes = []
>>> for symbol in symbols:
... codes.append(ord(symbol))
...
>>> codes
[36, 162, 163, 165, 8364, 164]
>>> symbols = '$¡é¡ê£¤€¡è'
>>> codes = [ord(symbol) for symbol in symbols]
>>> codes
[36, 162, 163, 165, 8364, 164]
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2.2.3 µÑ¿¨¶û»ý
´úÂë2-4 ʹÓÃÁбíÍƵ¼¼ÆËãµÑ¿¨¶û»ý
>>> colors = ['black', 'white']
>>> sizes = ['S', 'M', 'L']
>>> tshirts = [(color, size) for color in colors for size in sizes]
>>> tshirts
[('black', 'S'), ('black', 'M'), ('black', 'L'), ('white', 'S'),
('white', 'M'), ('white', 'L')]
>>> for color in colors:
... for size in sizes:
... print((color, size))
...
('black', 'S')
('black', 'M')
('black', 'L')
('white', 'S')
('white', 'M')
('white', 'L')
>>> tshirts = [(color, size) for size in sizes
... for color in colors]
>>> tshirts
[('black', 'S'), ('white', 'S'), ('black', 'M'), ('white', 'M'),
('black', 'L'), ('white', 'L')]
2.2.4 Éú³ÉÆ÷±í´ïʽ
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´úÂë2-5 ʹÓÃÉú³ÉÆ÷±í´ïʽ
>>> symbols = '$¡é¡ê£¤€¡è'
>>> tuple(ord(symbol) for symbol in symbols) ?
(36, 162, 163, 165, 8364, 164)
>>> import array
>>> array.array('I', (ord(symbol) for symbol in symbols)) ?
array('I', [36, 162, 163, 165, 8364, 164])
>>> colors = ['black', 'white']
>>> sizes = ['S', 'M', 'L']
>>> for tshirt in ('%s %s' % (c, s) for c in colors for s in sizes): ?
... print(tshirt)
...
black S
black M
black L
white S
white M
white L
2.3 Ôª×é
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2.3.1 Ôª×éºÍ¼Ç¼
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