all Python 3bz2term

bz2.BZ2File

files

A file object for reading and writing bzip2-compressed data in binary mode. It takes a file name or an already open file.

Syntax

f = bz2.BZ2File(filename, mode='r', *, compresslevel=9)

BZ2File handles bytes only: mode 'rt' or 'wt' gives ValueError — for text use bz2.open(), which wraps the file in a TextIOWrapper for you. Mode 'a' does not extend the existing stream but appends a new one; reading joins the streams transparently. Without closing it (with) the tail of the compressed data never reaches the disk.

Examples

import bz2
with bz2.BZ2File('log.bz2', 'w') as f:
    f.write(b'first ')
with bz2.BZ2File('log.bz2', 'a') as f:
    f.write(b'second')
with bz2.BZ2File('log.bz2') as f:
    print(f.read())  # → b'first second'

import bz2
try:
    bz2.BZ2File('x.bz2', 'wt')
except ValueError as e:
    print(e)  # → Invalid mode: 'wt'

See also

Common errors

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