’’‘read files’’'

with open('pi_digits.txt') as file_object:
    contents = file_object.read()
    print(contents)
    print(contents.rstrip())
    for line in file_object:
        print(line.rstrip() + ".\n")

’’‘must reopen once’’'

with open('pi_digits.txt') as file_object:
    lines = file_object.readlines()
    pi_string =''
    for line in lines:
        pi_string +=line.rstrip()
    print(pi_string)
    print(len(pi_string))

with open('/users/apple/Desktop/pi_digits.txt') as file_object:
    contents = file_object.read()
    print(contents)
    print(contents.rstrip())
    lines = file_object.readlines()
for line in lines:
    print(line.rstrip() + ".\n")

’’‘write files’’'

filename = 'programming.txt'
with open(filename, 'w') as file_object:
    file_object.write("I love programming!")
    file_object.write("\nI don't means that meaning!")
with open(filename, 'a') as file_object:
    file_object.write("\nwhat do you meaning!\n")
    file_object.write("I just use it make money!")

实验结果：
================ RESTART: /Users/apple/Documents/FileRead.py ================
3.1415926535
8979323846
2643383279
3.1415926535
8979323846
2643383279
3.141592653589793238462643383279
32
3.1415926535
8979323846
2643383279
3.1415926535
8979323846
2643383279