10-1至10-13

file_name = 'text.txt'

with open(file_name) as file_object:
contents = file_object.read()
print(contents)

with open(file_name) as file_object:
for line in file_object:
print(line.rstrip())

with open(file_name) as file_object:
lines = file_object.readlines()

for line in lines:
print(line.rstrip())

file_name = 'text.txt'

with open(file_name) as file_object:
lines = file_object.readlines()

for line in lines:
print(line.replace('Python', 'C').rstrip())

file_name = 'guest.txt'

name = input("What's your name?")

with open(file_name, 'w') as file_object:
file_object.write(name)

file_name = 'guest.txt'
while 1:
name = input("What's your name?")
if name == 'q':
break
with open(file_name, 'a') as file_object:
file_object.write(name)

try:
x = input('write down a number')
y = input('write dow another number')
print('the sum is ' + str(int(x) + int(y)))
except ValueError:
print('sorry, please write down a number.')

while 1:
try:
x = input('write down a number')
if x == 'q':
break
y = input('write dow another number')
if y == 'q':
break
print('the sum is ' + str(int(x) + int(y)))
except ValueError:
print('sorry, please write down a number.')

file_name = 'cats.txt'
try:
print("cats' name:")
with open(file_name) as file_object:
for line in file_object:
print(line.rstrip())
except FileNotFoundError:
print('sorry, there is not file ' + file_name)
file_name = 'dogs.txt'
try:
print("dogs' name:")
with open(file_name) as file_object:
for line in file_object:
print(line.rstrip())
except FileNotFoundError:
print('sorry, there is not file ' + file_name)

file_name = 'cats.txt'
try:
print("cats' name:")
with open(file_name) as file_object:
for line in file_object:
print(line.rstrip())
except FileNotFoundError:
print('sorry, there is not file ' + file_name)
file_name = 'dogs.txt'
try:
print("dogs' name:")
with open(file_name) as file_object:
for line in file_object:
print(line.rstrip())
except FileNotFoundError:
pass

import json
file_name = 'save.json'
try:
with open(file_name) as file_object:
num = json.load(file_object)
print("I know your favorite number! It's " + str(num))
except FileNotFoundError:
number = input("What's your favorite number?")
with open(file_name, 'w') as file_object:
json.dump(number, file_object)