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Open compressed files transparently

Project Description
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This small Python module provides a ``xopen`` function that works like the
built-in ``open`` function, but can also deal with compressed files.
Supported compression formats are gzip, bzip2 and xz. They are automatically
recognized by their file extensions `.gz`, `.bz2` or `.xz`.

The focus is on being as efficient as possible on all supported Python versions.
For example, simply using ```` is very slow in older Pythons, and
it is a lot faster to use a ``gzip`` subprocess. For writing to gzip files,
``xopen`` uses ``pigz`` when available.

This module has originally been developed as part of the `cutadapt
tool <>`_ that is used in bioinformatics to
manipulate sequencing data. It has been in successful use within that software
for a few years.

``xopen`` is compatible with Python 2.6, 2.7, 3.3, 3.4, 3.5 and 3.6.


Open a file for reading::

from xopen import xopen

with xopen('file.txt.xz') as f:
content =

Or without context manager::

from xopen import xopen

f = xopen('file.txt.xz')
content =

Open a file for writing::

from xopen import xopen

with xopen('file.txt.gz', mode='w') as f:


The name ``xopen`` was taken from the C function of the same name in the
`utils.h file which is part of BWA <>`_.

Kyle Beauchamp <> has contributed support for appending to files.

Some ideas were taken from the `canopener project <>`_.
If you also want to open S3 files, you may want to use that module instead.


Marcel Martin <> (`@marcelm_ on Twitter <>`_)


* `Source code <>`_
* `Report an issue <>`_
* `Project page on PyPI (Python package index) <>`_
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File Name & Checksum SHA256 Checksum Help Version File Type Upload Date
xopen-0.3.0-py2.py3-none-any.whl (6.5 kB) Copy SHA256 Checksum SHA256 py2.py3 Wheel Nov 15, 2017
xopen-0.3.0.tar.gz (4.5 kB) Copy SHA256 Checksum SHA256 Source Nov 15, 2017

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