文件操作

fw = open('plainText.txt',mode='w',encoding='utf-8')
for c in plainText:
    print(chr(ord(c)+3),end='')
    fw.write(chr(ord(c)+3))

name1 = 'Peter'
name2 = 'Kate'
people = ['Peter','Kate','Lisa',12]
people.append('Ez')
people.insert(2,'Anne')
print(len(people),people)

fr = open('plainText.txt',mode='r',encoding='utf-8')
plainText = fr.read()
print(plainText)
print('密文：',end='')
for c in plainText:
    print(chr(ord(c)+3),end='')


fw =open('cipherText.txt',mode='a',encoding='utf-8')
for c in plainText:
   print(chr(ord(c)+3),end='')
   fw.write(chr(ord(c)+3))
fr.close()
fw.close()