Python save console output to file

In normal work, sometimes we need to save the console output to a file

1. Command line with> overwrite and >> append write

for i in range(10000):
    print(i)

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#Write the console output override to the file python myprint.py> myprint.txt

#Append the console output to the file python myprint.py >> myprint.txt

2. Output sys.stdout to a file

import sys
import time
f=open("myprint.txt","w+")
sys.stdout=f
for i in range(1000):
    print(i*9)

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Disadvantages: can only be saved to a file, but the console has no output

3. Use the file parameter in the print function

import sys
import time
f=open("myprint.txt","w+")
for i in range(100):
    print("--{}--".format(i**2),file=f,flush=True)
    print("--{}--".format(i ** 2),file=sys.stdout)
    time.sleep(0.5)

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Save the output from the console to a file instantly

The file parameter in the print function, file = f, output to file; file = sys.stdout, output to terminal; flush = True, instant refresh

4. Implement with classes

import sys
class Logger(object):
    def __init__(self, filename='default.log', stream=sys.stdout):
        self.terminal = stream
        self.log = open(filename, 'a')

    def write(self, message):
        self.terminal.write(message)
        self.log.write(message)

    def flush(self):
        pass

sys.stdout = Logger(stream=sys.stdout)

# now it works
print('print something')
print("output")

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