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:mod:`!tomllib` --- Parse TOML files

.. module:: tomllib
   :synopsis: Parse TOML files.

Source code: :source:`Lib/tomllib`

This module provides an interface for parsing TOML 1.1.0 (Tom's Obvious Minimal Language, https://toml.io). This module does not support writing TOML.

.. versionadded:: 3.11
   The module was added with support for TOML 1.0.0.


.. versionchanged:: 3.15
   Added TOML 1.1.0 support.
   See the :ref:`What's New <whatsnew315-tomllib-1-1-0>` for details.

Note

Be cautious when parsing data from untrusted sources. A malicious TOML string may cause the decoder to consume considerable CPU and memory resources. Limiting the size of data to be parsed is recommended.

.. seealso::

    The :pypi:`Tomli-W package <tomli-w>`
    is a TOML writer that can be used in conjunction with this module,
    providing a write API familiar to users of the standard library
    :mod:`marshal` and :mod:`pickle` modules.


.. seealso::

    The :pypi:`TOML Kit package <tomlkit>`
    is a style-preserving TOML library with both read and write capability.
    It is a recommended replacement for this module for editing already
    existing TOML files.

This module defines the following functions:

.. function:: load(fp, /, *, parse_float=float)

   Read a TOML file. The first argument should be a readable and binary file object.
   Return a :class:`dict`. Convert TOML types to Python using this
   :ref:`conversion table <toml-to-py-table>`.

   *parse_float* will be called with the string of every TOML
   float to be decoded.  By default, this is equivalent to ``float(num_str)``.
   This can be used to use another datatype or parser for TOML floats
   (e.g. :class:`decimal.Decimal`). The callable must not return a
   :class:`dict` or a :class:`list`, else a :exc:`ValueError` is raised.

   A :exc:`TOMLDecodeError` will be raised on an invalid TOML document.



.. function:: loads(s, /, *, parse_float=float)

   Load TOML from a :class:`str` object. Return a :class:`dict`. Convert TOML
   types to Python using this :ref:`conversion table <toml-to-py-table>`. The
   *parse_float* argument has the same meaning as in :func:`load`.

   A :exc:`TOMLDecodeError` will be raised on an invalid TOML document.

The following exceptions are available:

.. exception:: TOMLDecodeError(msg, doc, pos)

   Subclass of :exc:`ValueError` with the following additional attributes:

   .. attribute:: msg

      The unformatted error message.

   .. attribute:: doc

      The TOML document being parsed.

   .. attribute:: pos

      The index of *doc* where parsing failed.

   .. attribute:: lineno

      The line corresponding to *pos*.

   .. attribute:: colno

      The column corresponding to *pos*.

   .. versionchanged:: 3.14
      Added the *msg*, *doc* and *pos* parameters.
      Added the :attr:`msg`, :attr:`doc`, :attr:`pos`, :attr:`lineno` and :attr:`colno` attributes.

   .. deprecated:: 3.14
      Passing free-form positional arguments is deprecated.

Examples

Parsing a TOML file:

import tomllib

with open("pyproject.toml", "rb") as f:
    data = tomllib.load(f)

Parsing a TOML string:

import tomllib

toml_str = """
python-version = "3.11.0"
python-implementation = "CPython"
"""

data = tomllib.loads(toml_str)

Conversion Table

TOML Python
TOML document dict
string str
integer int
float float (configurable with parse_float)
boolean bool
offset date-time datetime.datetime (tzinfo attribute set to an instance of datetime.timezone)
local date-time datetime.datetime (tzinfo attribute set to None)
local date datetime.date
local time datetime.time
array list
table dict
inline table dict
array of tables list of dicts