文件操作

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()

name1 = 'Ava'
name2 = 'Sophia'
classmates = ['Lucas','Grace','Thomas','Logan']
classmates.append('Ella')

print(len(classmates),classmates)

name1 = 'Ava'
name2 = 'Sophia'
classmates = ['Lucas','Grace','Thomas','Logan']
classmates.append('Ella')
classmates.insert(1,'Colin')

print(len(classmates),classmates)

name1 = 'Ava'
name2 = 'Sophia'
classmates = ['Lucas','Grace','Thomas','Logan']
classmates.append('Ella')
classmates.insert(1,'Colin')
classmates.pop()

print(len(classmates),classmates)

name1 = 'Ava'
name2 = 'Sophia'
classmates = ['Lucas','Grace','Thomas','Logan']
classmates.append('Ella')
classmates.insert(1,'Colin')
classmates.pop()
classmates.pop(4)
print(len(classmates),classmates)

name1 = 'Ava'
name2 = 'Sophia'
classmates = ['Lucas','Grace','Thomas','Logan']
classmates.append('Ella')
classmates.insert(1,'Colin')
classmates.pop()
classmates.pop(4)
classmates[0] = 'Ella'
print(len(classmates),classmates)