>>> import re
>>> pattern = re.compile(r'bat|bit')
>>> r1 = re.match(pattern,'bat bet bit')
>>> r1
<re.Match object; span=(0, 3), match='bat'>
>>> print(r1.group())
bat

>>> re.match('foo','foo').group()
'foo'
>>> re.match('fo.','foo').group()
'foo'
>>> re.match('fo.','food on the table').group()
'foo'
>>> re.match('fo.','ffood on the table').group()
Traceback (most recent call last):
  File "<stdin>", line 1, in <module>
AttributeError: 'NoneType' object has no attribute 'group'
>>> re.match('.fo.','ffood on the table').group()
'ffoo'
>>> re.match('\w*fo.','ffood on the table').group()
'ffoo'
>>> re.match('\w*d.','ffood on the table').group()
'ffood '
>>> re.match('\w*d','ffood on the table').group()
'ffood'
>>> re.match('\w* on','ffood on the table').group()
'ffood on'

>>> re.match('on','ffood on the table').group()# match() 匹配失败
Traceback (most recent call last):
  File "<stdin>", line 1, in <module>
AttributeError: 'NoneType' object has no attribute 'group'
>>> re.search('on','ffood on the table').group()# search() 匹配成功
'on'
>>> re.search('on t','ffood on the table').group()
'on t'
>>> re.search('on t..','ffood on the table').group()
'on the'

>>> bt = 'bat|bet|bit'# 正则表达式模式：bat、bet、bit
>>> m = re.match(bt,'bat')# 'bat' 匹配 成功
>>> if m is not None:m.group()
...
'bat'
>>> m = re.match(bt,'bwt')# 'bwt' 匹配 失败
>>> if m is not None:m.group()
...
>>> m = re.match(bt,'He bit me!')# 无法匹配
>>> if m is not None:m.group()
...
>>> m = re.search(bt,'He bit me!')# 通过搜索，找到 'bit' ，匹配成功
>>> if m is not None:m.group()
...
'bit'

>>> import re
>>> anyend = '.end'
>>> m = re.match(anyend,'bend')         # 点号匹配 'b'
>>> if m is not None: m.group()
...
'bend'
>>> m = re.match(anyend,'end')         # 匹配失败 空字符
>>> if m is not None: m.group()
...
>>> m = re.match(anyend,'\nend')       # 匹配失败 \n
>>> if m is not None: m.group()
...
>>> m = re.search(anyend,'The end.')   # 搜索方式匹配到空格字符 ' '
>>> if m is not None: m.group()
...
' end'

>>> patt314 = '3.14'
>>> pi_patt = '3\.14'
>>> m = re.match(pi_patt, '3.14')
>>> if m is not None: m.group()
...
'3.14'
>>> m = re.match(patt314, '3.14')
>>> if m is not None: m.group()
...
'3.14'
>>> m = re.match(patt314, '3214')
>>> if m is not None: m.group()
...
'3214'

>>> m=re.match('(\w\w\w)-(\d\d\d)','abc-123')
>>> m.group()         # 完整匹配
'abc-123'
>>> m.group(1)        # 子组1
'abc'
>>> m.group(2)        # 子组2
'123'
>>> m.groups()        # 所有子组
('abc', '123')

#--------------------------------------
>>> m=re.match('ab','ab')     # 没有子组
>>> m.group()                 # 完整匹配
'ab'
>>> m.groups()                # 所有子组
()
#--------------------------------------
>>> m=re.match('(ab)','ab')   # 一个子组
>>> m.group()                 # 完整匹配
'ab'
>>> m.group(1)                # 子组1
'ab'
>>> m.groups()                # 所有子组
('ab',)
#--------------------------------------
>>> m=re.match('(a)(b)','ab')   # 两个子组
>>> m.group()                   # 完整匹配
'ab'
>>> m.group(1)                  # 子组1
'a'
>>> m.group(2)                  # 子组2
'b'
>>> m.groups()                  # 所有子组
('a', 'b')
#--------------------------------------
>>> m=re.match('(a(b))','ab')   # 两个子组
>>> m.group()                   # 完整匹配
'ab'
>>> m.group(1)                  # 子组1
'ab'
>>> m.group(2)                  # 子组2
'b'
>>> m.groups()                  # 所有子组
('ab', 'b')

>>> import re
>>> m=re.search('^The','The end.')          # 起始匹配
>>> if m is not None: m.group()
...
'The'
>>> m=re.search(r'dog$','bitethe dog')      # 结尾匹配
>>> if m is not None: m.group()
...
'dog'
>>> m=re.search('^The','end. The')          # 非起始，不匹配 注意大小写匹配
>>> if m is not None: m.group()
...
>>> m=re.search(r'\bthe','bite the dog')    # 在边界，匹配 注意大小写匹配
>>> if m is not None: m.group()
...
'the'
>>> m=re.search(r'\bthe','bitethe dog')     # 非边界 不匹配
>>> if m is not None: m.group()
...
>>> m=re.search(r'\Bthe','bitethe dog')     # 非边界 匹配非边界
>>> if m is not None: m.group()
...
'the'

>>> re.findall('car','car')
['car']
>>> re.findall('car','scary')
['car']
>>> re.findall('car','scary the barcardi to the car')
['car', 'car', 'car']

>>> import os
>>> os.system('clear')

0
>>>

>>> import os
>>> t = os.system('clear')

>>>

python -m py_compile file.py
python -m py_compile /root/src/{file1,file2}.py

import py_compile
py_compile.compile('path') //path是包括.py文件名的路径

python -m compileall /root/src/

import compileall
compileall.compile_dir(r'H:\game')

if x > y:       # 可以没有 ()，也可以有
    x = 1
    y = 2

>>> bool('-1')
True
>>> bool(-1)
True
>>> bool(0)
False
>>> bool('')
False
>>> bool(None)
False

>>> 'bat' in ['cat','bat','rat','elephant']
True
>>> 'dog' in ['cat','bat','rat','elephant']
False
>>> 'dog' not in ['cat','bat','rat','elephant']
True
>>> not 'dog' in ['cat','bat','rat','elephant']
True

>>> x = 6
>>> if x > 10:
...     print('>10')
... elif x == 10:
...     print('=10')
... else:
...     print('<10')
...
<10

>>> for c in 'spam':
...     print(c.upper())
...
S
P
A
M

>>> for i in range(1,10):
...     for j in range(1,10):
...         print('{} X {} = {}'.format(i,j,i*j))
...
1 X 1 = 1
1 X 2 = 2
1 X 3 = 3
...
9 X 9 = 81

>>> x=4
>>> while x>0:
...     print('spam!' * x)
...     x-=1
...
spam!spam!spam!spam!
spam!spam!spam!
spam!spam!
spam!

>>> x=5
>>> while x > 0:
...     x -= 1
...     if x == 4:
...         continue
...     elif x == 1:
...         break
...     else:
...         print('spam!' * x)
...
spam!spam!spam!
spam!spam!

def spam():
    eggs = 222


spam()
print(eggs)

Traceback (most recent call last):
  File "g:/WaProj/PyHello/test.py", line 20, in <module>
    print(eggs)
NameError: name 'eggs' is not defined

def spam():
    eggs = 99
    bacon()
    print(eggs)


def bacon():
    ham = 101
    eggs = 0


spam()

99

def spam():
    print(eggs)


eggs = 42
spam()
print(eggs)

42
42

def spam():
    eggs = 11
    print(eggs)


eggs = 42
spam()
print(eggs)

11
42

def spam():
    print(eggs)
    eggs = 11


eggs = 42
spam()
print(eggs)

Traceback (most recent call last):
  File "g:/WaProj/PyHello/test.py", line 7, in <module>
    spam()
  File "g:/WaProj/PyHello/test.py", line 2, in spam
    print(eggs)
UnboundLocalError: local variable 'eggs' referenced before assignment

def spam():
    global eggs
    eggs = 'spam'

eggs = 'global'
spam()
print(eggs)

spam

def spam(divideBy):
    return 42 / divideBy

try:
    print(spam(2))
    print(spam(12))
    print(spam(0))
    print(spam(1))
except ZeroDivisionError:
    print('Error: Invalid argument.')

21.0
3.5
Error: Invalid argument.

def spam(divideBy):
    try:
        return 42 / divideBy
    except ZeroDivisionError:
        print('Error:无效参数')

print(spam(2))
print(spam(12))
print(spam(0))
print(spam(1))

21.0
3.5
Error:无效参数
None
42.0

>>> '%s,bbb,%s' % ('aaa','ccc')#格式化表达式
'aaa,bbb,ccc'

>>> '{0},bbb,{1}'.format('aaa','ccc')#格式化方法(2.6，3.0)
'aaa,bbb,bbb'
>>> '{1},bbb,{0}'.format('aaa','ccc')   # 位置变化
'ccc,bbb,aaa'
>>> '{},bbb,{}'.format('aaa','ccc')
'aaa,bbb,ccc'
>>> '{},bbb,{c:.2f}'.format('aaa',c=2)#:f 小数表示为定点数
'aaa,bbb,2.00'
>>> '{},bbb,{c:b}'.format('aaa',c=55)#:b 整数表示为二进制数
'aaa,bbb,110111'

>>> a='Python'
>>> f'Hello {a}'
'Hello Python'

>>> from string import Template
>>> Template('Hello $who and $terminal').substitute(who='Python',terminal='Cmder')
'Hello Python and Cmder'

>>> '/'.join(['','usr','bin','env'])
'/usr/bin/env'
>>> '/'.join(('','usr','bin','env'))
'/usr/bin/env'

>>> '/usr/bin/env'.split('/')
['', 'usr', 'bin', 'env']

>>> s='12345654321'
>>> s[0:1]
'1'
>>> s[0:2]
'12'
>>> s[1:2]
'2'
>>> s[1:3]
'23'
>>> s[-1]
'1'
>>> s[-5:]
'54321'
>>> s[:-5]
'123456'

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

>>> for v in range(1,5):
...     print(v)
...
1
2
3
4

>>> r=[]
>>> for v in range(1,5):
...     r.append(v**2)
...
>>> print(r)
[1, 4, 9, 16]

>>> [v**2 for v in range(1,5)]
[1, 4, 9, 16]

>>> r=0
>>> for v in range(1,5):
...     r+=v
...
>>> r
10

>>> sum(range(1,5))
10
>>> min(range(1,5))
1
>>> max(range(1,5))
4

>>> cat = ['fat','black','looud']
>>> size = cat[0]
>>> color = cat[1]
>>> disposition = cat[2]

>>> cat = ['fat','black','looud']
>>> size,color,disposition = cat

>>> spam=['cat','bat','rat','elephant']
>>> del spam[2]
>>> spam
['cat', 'bat', 'elephant']
>>> del spam[2]
>>> spam
['cat', 'bat']

>>> cat = ['fat','black','looud']
>>> cat.remove('black')
>>> cat
['fat', 'looud']

>>> eggs=('hello',42,0.5)
>>> eggs
('hello', 42, 0.5)
>>> eggs[0]
'hello'
>>> eggs[1:3]
(42, 0.5)
>>> len(eggs)
3

>>> type(('hello',))
<class 'tuple'>
>>> type(('hello'))
<class 'str'>

>>> list(('hello',42,0.5))
['hello', 42, 0.5]
>>> tuple(['hello',42,0.5])
('hello', 42, 0.5)
>>> list('hello')
['h', 'e', 'l', 'l', 'o']
>>> tuple('hello')
('h', 'e', 'l', 'l', 'o')

>>> spam='a'
>>> cheese=11
>>> cheese=spam
>>> spam=100
>>> spam
100
>>> cheese
'a'

>>> spam=[0,1,2,3,4,5]
>>> cheese=spam
>>> cheese[1]='hi'
>>> spam
[0, 'hi', 2, 3, 4, 5]
>>> cheese
[0, 'hi', 2, 3, 4, 5]
>>> spam[3]='ah'
>>> spam
[0, 'hi', 2, 'ah', 4, 5]
>>> cheese
[0, 'hi', 2, 'ah', 4, 5]

>>> spam = list('ABCD')
>>> spam
['A', 'B', 'C', 'D']
>>> cheese = copy.copy(spam)
>>> cheese[1] = 22
>>> cheese
['A', 22, 'C', 'D']
>>> spam
['A', 'B', 'C', 'D']

# 常见方式
>>> d={'name':'wa','age':20}
>>> d
{'name': 'wa', 'age': 20}

# 另一种创建方式
>>> d={}
>>> d['name']='wa'
>>> d['age']=20
>>> d
{'name': 'wa', 'age': 20}

# dict() 函数
>>> dict([('name','wa'),('age',20)])# []可以
{'name': 'wa', 'age': 20}
>>> dict({('name','wa'),('age',20)})# {}也可以
{'age': 20, 'name': 'wa'}

>>> d={'name':'wa','age':20}
>>> d['name']
'wa'
>>> d['name'] + ' ' + str(d['age']) + ' 岁了！'
'wa 20 岁了！'
>>>

>>> d={'name':'wz','first':'z','last':'w'}
>>> for k,v in d.items():# items()
...     print('  Key: ' + k)
...     print('Value: ' + v+'\n')
...
  Key: name
Value: wz

  Key: first
Value: z

  Key: last
Value: w

>>> for k in d.keys():# 遍历所有 键 keys()
...     print('  Key: ' + k.title())
...
  Key: Name
  Key: First
  Key: Last

>>> for v in d.values():# 遍历所有 值 values()
...     print(v.title())
...
Wz
Z
W

>>> d={'name':'wz','first':'z','last':'w'}
>>> 'name' in d.keys()
True
>>> 'w' in d.values()
True
>>> 'first' in d.values()
False
>>> 'first' not in d.values()
True

>>> n=['first']
>>> for k in d.keys():
...     print(k.title())
...     if k in n:# 嵌套 if 判断
...         print('        z')
...
Name
First
        z
Last

>>> d={'name':'wz','first':'z','last':'w'}
>>> d.get('last','wang')
'w'
>>> d.get('all','wang')
'wang'
>>>

>>> d={'name':'wz','first':'z','last':'w'}
>>> d.setdefault('all','wazz')
'wazz'
>>> d
{'name': 'wz', 'first': 'z', 'last': 'w', 'all': 'wazz'}
>>>

>>> message = 'It was a bright cold day in April, and the clocks were striking thirteen.'
>>> count = {}
>>>
>>> for character in message:
...     count.setdefault(character, 0)
...     count[character] = count[character] + 1
...
>>> print(count)
{'I': 1, 't': 6, ' ': 13, 'w': 2, 'a': 4, 's': 3, 'b': 1, 'r': 5, 'i': 6, 'g': 2, 'h': 3, 'c': 3, 'o': 2, 'l': 3, 'd': 3, 'y': 1, 'n': 4, 'A': 1, 'p': 1, ',': 1, 'e': 5, 'k': 2, '.': 1}

>>> import pprint
>>> message = 'It was a bright cold day in April, and the clocks were striking thirteen.'
>>> count = {}
>>>
>>> for character in message:
...     count.setdefault(character, 0)
...     count[character] = count[character] + 1
...
>>> pprint.pprint(count)
{' ': 13,
 ',': 1,
 '.': 1,
 'A': 1,
 'I': 1,
 'a': 4,
 'b': 1,
 'c': 3,
 'd': 3,
 'e': 5,
 'g': 2,
 'h': 3,
 'i': 6,
 'k': 2,
 'l': 3,
 'n': 4,
 'o': 2,
 'p': 1,
 'r': 5,
 's': 3,
 't': 6,
 'w': 2,
 'y': 1}

>>> def func():
...     print('简单函数！')
...
>>> func()
简单函数！

>>> def func(para):
...     print('简单函数！' + para)
...
>>> func('这是参数')                # 位置实参
简单函数！这是参数
>>> func(para='这是参数')           # 关键字实参
简单函数！这是参数

>>> def func(para='默认参数值'):    # 默认值
...     print('简单函数！' + para)
...
>>> func()                         # 使用默认值
简单函数！默认参数值

>>> def func(*para):               # 任意数量实参
...     print('任意数量！')
...     print(para)
...
>>> func('1')
任意数量！
('1',)
>>> func('1','2')
任意数量！
('1', '2')

def func2(para='默认参数值'):
    print('简单函数！' + para)


def func(*para):
    print(para)

>>> import test
>>> test.func('a')              # 必须指定前缀
('a',)
>>> test.func('a','b','c')      # 必须指定前缀
('a', 'b', 'c')
>>> test.func2()                # 必须指定前缀
简单函数！默认参数值

>>> from test import func
>>> func('a','b')               # 不需要指定前缀
('a', 'b')
>>> func2                       # 没有导入 func2 ,出错
Traceback (most recent call last):
  File "<stdin>", line 1, in <module>
NameError: name 'func2' is not defined

>>> from test import func,func2
>>> func('a','b')               # 可以不指定前缀
('a', 'b')
>>> func2()                     # 可以不指定前缀
简单函数！默认参数值

>>> from test import *

class Dog():
    def __init__(self, name, age):
        self.name = name
        self.age = age

    def sleep(self):
        print(self.name.title() + " 正在睡觉...")

    def playgame(self):
        print(self.name.title() + " 游戏中...")

    def getage(self):
        print(self.name.title() + " " + str(self.age) + " 岁了!")

    def setage(self, age):
        self.age = age

>>> import test
>>> mydog=test.Dog('huahua',2)      # 创建实例
>>> mydog.name                      # 访问属性
'huahua'
>>> mydog.age
2
>>> mydog.sleep()                   # 调用方法
Huahua 正在睡觉...
>>> mydog.playgame()
Huahua 游戏中...
>>> mydog.getage()
Huahua 2 岁了!
>>> mydog.age=3                     # 直接修改实例的属性值
>>> mydog.age
3
>>> mydog.color="black"             # 在实例内产生全新的属性，之前在类中并没有定义过
>>> mydog.color
'black'
>>> mydog.getage()
Huahua 3 岁了!
>>> mydog.setage(5)                 # 调用方法修改属性值
>>> mydog.age
5
>>> mydog.getage()
Huahua 5 岁了!

class Dog():                        # 超类
    def __init__(self, name, age):
        self.name = name
        self.age = age

    def sleep(self):
        print(self.name.title() + " 正在睡觉...")

    def playgame(self):
        print(self.name.title() + " 游戏中...")

    def getage(self):
        print(self.name.title() + " " + str(self.age) + " 岁了!")

    def setage(self, age):
        self.age = age

class LittleDog(Dog):               # 创建继承类（子类：LittleDog，超类：Dog）
    def setage(self, age):          # 重写父类方法
        if 0 < age <= 3:
            self.age = age
        else:
            print('不合适的小狗年龄！')

>>> import test
>>> mydog=test.LittleDog('huahua',2)
>>> mydog.name
'huahua'
>>> mydog.age
2
>>> mydog.getage()
Huahua 2 岁了!
>>> mydog.setage(3)
>>> mydog.getage()
Huahua 3 岁了!
>>> mydog.setage(6)
不合适的小狗年龄！

class Dog():
    def __init__(self, name, age):
        ...

class LittleDog(Dog):
    def __init__(self, name, age):
        super().__init__(name,age)
        ...

class Dog(object):
    def __init__(self, name, age):
        ...

class LittleDog(Dog):
    def __init__(self, name, age):
        super(LittleDog,self).__init__(name,age)
        ...

>>> class FirstClass:               # Define a class object
...     def setdata(self, value):   # Define class methods
...         self.data = value       # self is the instance
...     def display(self):
...         print(self.data)        # self.data: per instance
...
>>> class SecondClass(FirstClass):                   # Inherits setdata
...     def display(self):                           # Changes display
...         print('Current value = "%s"' % self.data)
...
>>> class ThirdClass(SecondClass):                     # Inherit from SecondClass
...     def __init__(self, value):                     # On "ThirdClass(value)"
...         self.data = value
...     def __add__(self, other):                      # On "self + other"
...         return ThirdClass(self.data + other)
...     def __str__(self):                             # On "print(self)", "str()"
...         return '[ThirdClass: %s]' % self.data
...     def mul(self, other):                          # In-place change: named 
...         self.data *= other
...
>>> a = ThirdClass('abc')           # __init__ called
>>> a.display()                     # Inherited method called
Current value = "abc"
>>> print(a)                        # __str__: returns display string
[ThirdClass: abc]

>>> b = a + 'xyz'                   # __add__: makes a new instance
>>> b.display()                     # b has all ThirdClass methods 
Current value = "abcxyz"
>>> print(b)                        # __str__: returns display string
[ThirdClass: abcxyz]

>>> a.mul(3)                        # mul: changes instance in-place
>>> print(a)
[ThirdClass: abcabcabc]

>>> class Test:
...     def prt(self):
...         print(self)
...         print(self.__class__)
...
>>> x = Test()
>>> x.prt()
<__main__.Test object at 0x000001F4E8C8FCF8>        # x 实例地址
<class '__main__.Test'>
>>> y = Test()
>>> y.prt()
<__main__.Test object at 0x000001F4E8C8FC88>        # y 实例地址
<class '__main__.Test'>

import random
rnum = random.randint(1, 20)
print('猜测1~20之间的一个数。')

for guessNum in range(1, 7):
    print('请输入猜测数字：')
    guess = int(input())

    if guess < rnum:
        print('小了')
    elif guess > rnum:
        print('大了')
    else:
        break

if guess == rnum:
    print('干得好！你用了 ' + str(guessNum) + '次机会猜对了结果。')
else:
    print('很遗憾，正确的数字是' + str(rnum))

def collatz(number):
    if number % 2 == 0:
        print(number//2)
        return number//2
    elif number % 2 == 1:
        print(3*number+1)
        return(3*number+1)

iInput = input('请输入一个整数：')
try:
    iReturn = collatz(int(iInput))
    while iReturn != 1:
        iReturn = collatz(int(iReturn))
except:
    print('输入的不是整数！')

def plst(lst):
    splst = "'"
    for i in range(1, len(lst)):
        splst += lst[i-1]+', '
    splst += 'and ' + lst[i] + "'"
    print(splst)

l = ['dog', 'cat', 'tiger', 'elephant']
plst(l)