>>> bool('I think,therefore I am')
True
>>> bool(10)
True
>>> bool('')
False
>>> bool(0)
False

>>> name = input('What is your name?')
What is your name?Gumby
>>> if name.endswith('Gumby'):print(name)Gumby

>>> name = input('What is your name?')
What is your name?Gumby
>>> if name.endswith('Gumby'):if name.startswith('Mr.'):print('Hello,Mr.Gumby')elif name.startswith('Mrs.'):print('Hello,Mrs.Gumby')else:print('Hello,Gumby')
else:print('Hello,stranger')Hello,Gumby

>>> x = y = [1,2,3]
>>> z = [1,2,3]
>>> x == y
True
>>> x == z
True
>>> x is y
True
>>> x is z
False
>>> #is检查两个对象是否相同（不是相等），变量x和y指向同一个列表，而z指向另一个列表（即使它们包含的值是一样的），这两个列表虽然相等，但并非同一个列表。

>>> ord('a')
97
>>> ord('v')
118
>>> chr(118)
'v'

>>> age = 10
>>> assert 0 < age < 11
>>> age = -1
>>> assert 0 < age < 11
Traceback (most recent call last):File "<pyshell#47>", line 1, in <module>assert 0 < age < 11
AssertionError
>>> age = -1
>>> assert 0 < age < 11,'the age must be realistic' #字符串对断言做出说明
Traceback (most recent call last):File "<pyshell#49>", line 1, in <module>assert 0 < age < 11,'the age must be realistic' #字符串对断言做出说明
AssertionError: the age must be realistic

>>> name = ''
>>> while not name.strip():        #屏蔽空格name = input('please enter your name:')print('hello,{}!'.format(name))please enter your name:Momo
hello,Momo!

>>> numbers = [0,1,2,3,4,5,6,7,8]
>>> for number in numbers:print(number)0
1
2
3
4
5
6
7
8

>>> range(0,10)
range(0, 10)
>>> list(range(0,10))  #范围[0,10)
[0, 1, 2, 3, 4, 5, 6, 7, 8, 9]
>>> range(10)     #如果只提供1个位置，将把这个位置视为结束位置，并假定起始位置为0
range(0, 10)
>>> for num in range(1,10):print(num)1
2
3
4
5
6
7
8
9

>>> d = dict(a=1,b=2,c=3)
>>> d
{'a': 1, 'b': 2, 'c': 3}
>>> for key in d:print(key,'to',d[key])a to 1
b to 2
c to 3

>>> for key,value in d.items():print(key,'to',value)a to 1
b to 2
c to 3
>>> d.items()
dict_items([('a', 1), ('b', 2), ('c', 3)])

>>> names = ['aaa','bbb','ccc']
>>> ages = [10,11,12]
>>> for i in range(len(names)):print(names[i],'is',ages[i],'years old')aaa is 10 years old
bbb is 11 years old
ccc is 12 years old

>>> list(zip(names,ages))
[('aaa', 10), ('bbb', 11), ('ccc', 12)]
>>> for name,age in zip(names,ages):print(name,'is',age,'years old')aaa is 10 years old
bbb is 11 years old
ccc is 12 years old

>>> list(zip(range(5),range(10)))
[(0, 0), (1, 1), (2, 2), (3, 3), (4, 4)]

>>> strings = ['aac','ddd','aa','ccc']
>>> for string in strings:if 'aa' in string:         #替换列表中所有包含子串‘aa’的字符串index = strings.index(string)    #在列表中查找字符串strings[index] = '[censored]'>>> strings
['[censored]', 'ddd', '[censored]', 'ccc']

>>> strings = ['aac','ddd','aa','ccc']
>>> index = 0
>>> for string in strings:if 'aa' in string:strings[index] = '[censored]'index += 1>>> strings
['[censored]', 'ddd', '[censored]', 'ccc']

>>> strings = ['aac','ddd','aa','ccc']
>>> for index,string in enumerate(strings):if 'aa' in string:strings[index] = '[censored]'
>>> strings
['[censored]', 'ddd', '[censored]', 'ccc']

>>> sorted([4,2,5,1,3])
[1, 2, 3, 4, 5]
>>> sorted('hello,world')   #sorted返回一个列表
[',', 'd', 'e', 'h', 'l', 'l', 'l', 'o', 'o', 'r', 'w']
>>> list(reversed('Hello,world'))   #reversed返回一个可迭代对象，
['d', 'l', 'r', 'o', 'w', ',', 'o', 'l', 'l', 'e', 'H']
>>> ''.join(reversed('Hello,world'))
'dlrow,olleH'
>>> sorted('aBc',key=str.lower)   #按照字母表排序，可以先转换为小写
['a', 'B', 'c']

>>> from math import sqrt
>>> for n in range(99,1,-1):   #找出2-100的最大平方值，从100向下迭代，找到第一个平方值后，跳出循环。步长为负数，让range向下迭代。root = sqrt(n)if root == int(root):    #开平方为整print(n)break81

>>> while True:    #while True导致循环永不结束word = input('enter your name:')if not word:break   #在if语句中加入break可以跳出循环print(word)enter your name:aa
aa
enter your name:bb
bb
enter your name:
>>> 

>>> [x*x for x in range(10)]
[0, 1, 4, 9, 16, 25, 36, 49, 64, 81]

>>> [x*x for x in range(10) if x%3 == 0]
[0, 9, 36, 81]

>>> girls = ['aaa','bbb','ccc']
>>> boys = ['crde','bosy','adeb']
>>> [b+'+'+g for b in boys for g in girls if b[0]==g[0]]
['crde+ccc', 'bosy+bbb', 'adeb+aaa']

>>> girls = ['aaa','bbb','ccc']
>>> boys = ['crde','bosy','adeb']
>>> letterGrils = {}
>>> for girl in girls:letterGrils.setdefault(girl[0],[]).append(girl)   #每项的键都是一个字母，值为该字母开头的女孩名字组成的列表>>> print([b+'+'+g for b in boys for g in letterGrils[b[0]]])
['crde+ccc', 'bosy+bbb', 'adeb+aaa']

>>> squares = {i:'{} squared is {}'.format(i,i**2) for i in range(10)}
>>> squares[8]
'8 squared is 64'