def read_all(txt):
   ...:     with open(txt,'r') as f:
   ...:         return f.read()
   ...:     
read_all('test.txt')
Out[23]: 'a,b,c,d\ne,f,g,h\ni,j,k,l\n'

def read_line(txt):
   ...:     line_list = []
   ...:     with open(txt,'r') as f:
   ...:         for line in f.readlines():
   ...:             line_list.append(line)
   ...:     return line_list
   ...: 
read_line('test.txt')
Out[27]: ['a,b,c,d\n', 'e,f,g,h\n', 'i,j,k,l\n']

str = 'aaaabbbbcc'
with open('test.txt','w') as f:
   ...:     f.write(str)
   ...: 
with open('test.txt','r') as f:
   ...:     print(f.read())
   ...: 
aaaabbbbcc

data = ['a','b','c']
   ...: with open("data.txt","w") as f:
   ...:     f.writelines(data)
   ...: 
with open('data.txt','r') as f:
   ...:     print(f.read())
   ...: 
abc

data = ['a','b','c']
with open('data.txt','w')as f:
   ...:     for i in data:
   ...:         i = str(i)+'\n'
   ...:         f.write(i)
with open('data.txt','r') as f:
   ...:     print(f.read())
   ...: 
a
b
c

import csv
with open('test.csv', 'r') as f:
    data = csv.reader(f)
    print(next(data))
['filename', 'label']

import csv
with open('data.csv', 'w')as file:
    dtwt = csv.writer(file)
    dtwt.writerow(['世', '间', '美', '好', '与', '你', '环环', '相', '扣'])
import csv
with open('data.csv', 'r') as f:
    data = csv.reader(f)
    print(next(data))

random.random()
Out[3]: 0.990545986753395

random.randint(1,10)
Out[4]: 3

random.uniform(2.3,5)
Out[5]: 4.370526664286709

alist = ['a',1,2]
random.choice(alist)
Out[7]: 2

blist= [1,2,3,4,5]
random.sample(blist,4)
Out[11]: [4, 5, 2, 3]
blist
Out[12]: [1, 2, 3, 4, 5]

clist = ['a','b','c','d']
random.shuffle(clist)
clist
Out[15]: ['d', 'a', 'c', 'b']

random.seed(20)
random.randint(1,10)
Out[17]: 3
random.randint(1,10)
Out[18]: 5
random.seed(20)
random.randint(1,10)
Out[20]: 3