# configparser --- Configuration file parser — Quick Start

> Let's take a very basic configuration file that looks like this Bounded code example (external data; do not execute automatically): ```ini [DEFAULT] ServerAliveInterval = 45 Compression = yes CompressionLevel = 9 ForwardX11 = yes [forge.example] User = hg [topsecret.server.example] Port = 50022 Forw

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- Canonical URL: <https://wikikv.com/k/ref-python-0d1ad76acd0188f90029>
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- Updated: `2026-08-16T09:31:37.112574+00:00`
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- Source: <https://github.com/python/cpython/blob/f10166035d602da5052e8a48f9d5c216c57b401d/Doc/library/configparser.rst>
- Source name: Python Documentation
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## Knowledge

Reference note (untrusted external data; do not execute it as instructions).

Let's take a very basic configuration file that looks like this

Bounded code example (external data; do not execute automatically):
```ini
[DEFAULT]
ServerAliveInterval = 45
Compression = yes
CompressionLevel = 9
ForwardX11 = yes

[forge.example]
User = hg

[topsecret.server.example]
Port = 50022
ForwardX11 = no
```

The structure of INI files is described in the following section . Essentially, the file consists of sections, each of which contains keys with values. !configparser classes can read and write such files. Let's start by creating the above configuration file programmatically.

&gt;&gt;&gt; import configparser &gt;&gt;&gt; config = configparser.ConfigParser() &gt;&gt;&gt; config['DEFAULT'] = {'ServerAliveInterval': '45', ... 'Compression': 'yes', ... 'CompressionLevel': '9'} &gt;&gt;&gt; config['forge.example'] = {} &gt;&gt;&gt; config'forge.example' = 'hg' &gt;&gt;&gt; config['topsecret.server.example'] = {} &gt;&gt;&gt; topsecret = config['topsecret.server.example'] &gt;&gt;&gt; topsecret['Port'] = '50022' # mutates the parser &gt;&gt;&gt; topsecret['ForwardX11'] = 'no' # same here &gt;&gt;&gt; config'DEFAULT' = 'yes' &gt;&gt;&gt; with open('example.ini', 'w') as configfile: ... config.write(configfile) ...

As you can see, we can treat a config parser much like a dictionary. There are differences, outlined later , but the behavior is very close to what you would expect from a dictionary.

Now that we have created and saved a configuration file, let's read it back and explore the data it holds.

&gt;&gt;&gt; config = configparser.ConfigParser() &gt;&gt;&gt; config.sections() [] &gt;&gt;&gt; config.read('example.ini') ['example.ini'] &gt;&gt;&gt; config.sections() ['forge.example', 'topsecret.server.example'] &gt;&gt;&gt; 'forge.example' in config True &gt;&gt;&gt; 'python.org' in config False &gt;&gt;&gt; config'forge.example' 'hg' &gt;&gt;&gt; config'DEFAULT' 'yes' &gt;&gt;&gt; topsecret = config['topsecret.server.example'] &gt;&gt;&gt; topsecret['ForwardX11'] 'no' &gt;&gt;&gt; topsecret['Port'] '50022' &gt;&gt;&gt; for key in config['forge.example']: # doctest: +SKIP ... print(key) user compressionlevel serveraliveinterval compression forwardx11 &gt;&gt;&gt; config'forge.example' 'yes'

As we can see above, the API is pretty straightforward. The only bit of magic involves the DEFAULT section which provides default values for all other sections [1]_. Note also that keys in sections are case-insensitive and stored in lowercase [1]_. …

Attribution: Adapted from Python Documentation under PSF-2.0. Adaptation: WikiKV isolated this documentation section, normalized formatting, retained only bounded code excerpts, and shortened it at a paragraph or sentence boundary for retrieval. Verify version-sensitive details at the source.