推导式构建字典

dic = {i:i**2 for i in range(10)}

re.sub('')

集合

set()

内部元素无序，不重复

dic = {i:words.count(i) for i in word}

lyric.split()。以空格切割

lyric.lower().  大写变小写

dic={i:i**2 for i in range(10)}

import re

lyric=re.sub('[,.?:;"\'],'',lyric)把标点符号变成空

统计lyric中的单词出现的频率

word=lyric.split()

word=set(words)

dic={i:words.count(i) for i in word}

import re
str="Each human being is born As something new, Something that never existed? before"
print(str)
str1=str.lower() #统一大小写
word=re.sub('[,?]',"",str1)#运用正则表达式替换掉句子中的特殊符号
words=word.split(" ") #以空格作为分隔符，将字符串转换为以单词为元素的列表
set1=set(words) #将列表转化为不包含重复元素的集合
dict={i:words.count(i) for i in set1}
print(dict)

lyric='the night begin'

字典的键值对

dic={i:i**2 for i in range()}

断句取词

words=lyric.split()

大写切换小写

import re

lylic='Words.......'

lylic.lower()

（符号）替换

lylic=re.sub（'[进行替换的对象],'替换成什么',对谁操作）

词频的统计

dic={i:word.counts(i) for i in word}

set()

集合：元素不重复，无序

lower