Read and write a file

The contents of the text file test.txt AAA BBB CCC DDD If

python


s = """\
AAA
BBB
DDD
DDD
"""
with open ('test.txt', 'r+') as f:
    print(f.read())
    f.seek(0)
    f.write(s)

Execution result


AAA
BBB
CCC
DDD

The contents of the text file test.txt are AAA BBB DDD DDD become.

r + is read + write. So If you don't have test.txt Unable to read An error will occur.

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