File Handling in Python

Open, read and write text and binary files with the with statement.

Beginner

with open("log.csv", "w", newline="") as f:
    f.write("time,voltage\n")
    f.write("0,3.3\n")

with open("log.csv") as f:
    for line in f:
        print(line.strip())

with closes the file automatically, even if an error occurs. Modes: "r" read, "w" write (overwrites), "a" append, add "b" for binary. For CSV and JSON use the csv and json modules; for paths use pathlib.Path.

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