title	description
isort configuration in MegaLinter	How to use isort (configure, ignore files, ignore errors, help & version documentations) to analyze PYTHON files

isort is the definitive Python import sorting tool that automatically organizes and standardizes import statements according to configurable rules. It serves as an essential companion to code formatters for maintaining clean, professional Python codebases.

Key Features:

Intelligent Import Grouping: Automatically separates standard library, third-party, and local imports into distinct sections
Alphabetical Sorting: Sorts imports within each group alphabetically for consistent ordering
Multiple Profiles: Built-in profiles for popular formatters (Black, Django, Google, etc.) ensuring seamless integration
Highly Configurable: Extensive configuration options for custom sorting rules, line lengths, and import styles
Multi-line Import Handling: Smart formatting of long import statements with various wrapping styles
Namespace Package Support: Proper handling of namespace packages and relative imports
Performance Optimized: Fast processing suitable for large codebases
Format Compatibility: Perfect integration with Black, autopep8, and other Python formatting tools
Diff Mode: Check-only mode for validation without modification

isort documentation

Version in MegaLinter: 7.0.0
Visit Official Web Site{target=_blank}
See How to configure isort rules{target=_blank}
- If custom .isort.cfg config file isn't found, .isort.cfg{target=_blank} will be used
See How to disable isort rules in files{target=_blank}

{target=_blank}

Configuration in MegaLinter

Enable isort by adding PYTHON_ISORT in ENABLE_LINTERS variable
Disable isort by adding PYTHON_ISORT in DISABLE_LINTERS variable
Enable autofixes by adding PYTHON_ISORT in APPLY_FIXES variable

Variable	Description	Default value
PYTHON_ISORT_ARGUMENTS	User custom arguments to add in linter CLI call Ex: `-s --foo "bar"`
PYTHON_ISORT_COMMAND_REMOVE_ARGUMENTS	User custom arguments to remove from command line before calling the linter Ex: `-s --foo "bar"`
PYTHON_ISORT_FILTER_REGEX_INCLUDE	Custom regex including filter Ex: `(src\|lib)`	Include every file
PYTHON_ISORT_FILTER_REGEX_EXCLUDE	Custom regex excluding filter Ex: `(test\|examples)`	Exclude no file
PYTHON_ISORT_CLI_LINT_MODE	Override default CLI lint mode - `file`: Calls the linter for each file - `list_of_files`: Call the linter with the list of files as argument - `project`: Call the linter from the root of the project	`list_of_files`
PYTHON_ISORT_FILE_EXTENSIONS	Allowed file extensions. `"*"` matches any extension, `""` matches empty extension. Empty list excludes all files Ex: `[".py", ""]`	`[".py", ".pyi", ".pyx", ".pxd"]`
PYTHON_ISORT_FILE_NAMES_REGEX	File name regex filters. Regular expression list for filtering files by their base names using regex full match. Empty list includes all files Ex: `["Dockerfile(-.+)?", "Jenkinsfile"]`	Include every file
PYTHON_ISORT_PRE_COMMANDS	List of bash commands to run before the linter	None
PYTHON_ISORT_POST_COMMANDS	List of bash commands to run after the linter	None
PYTHON_ISORT_UNSECURED_ENV_VARIABLES	List of env variables explicitly not filtered before calling PYTHON_ISORT and its pre/post commands	None
PYTHON_ISORT_CONFIG_FILE	isort configuration file name Use `LINTER_DEFAULT` to let the linter find it	`.isort.cfg`
PYTHON_ISORT_RULES_PATH	Path where to find linter configuration file	Workspace folder, then MegaLinter default rules
PYTHON_ISORT_DISABLE_ERRORS	Run linter but consider errors as warnings	`true`
PYTHON_ISORT_DISABLE_ERRORS_IF_LESS_THAN	Maximum number of errors allowed	`0`
PYTHON_ISORT_CLI_EXECUTABLE	Override CLI executable	`['isort']`

IDE Integration

Use isort in your favorite IDE to catch errors before MegaLinter !

IDE	Extension Name	Install
Emacs	py-isort.el	Visit Web Site{target=_blank}
vim	ale	Visit Web Site{target=_blank}
vim	vim-isort	Visit Web Site{target=_blank}
Visual Studio Code	VSCode Python Extension	Visit Web Site{target=_blank}

MegaLinter Flavors

This linter is available in the following flavors

Flavor	Description	Embedded linters
all	Default MegaLinter Flavor	127
cupcake	MegaLinter for the most commonly used languages	88
formatters	Contains only formatters	18
python	Optimized for PYTHON based projects	65

Behind the scenes

How are identified applicable files

File extensions: .py, .pyi, .pyx, .pxd

How the linting is performed

isort is called once with the list of files as arguments (list_of_files CLI lint mode)

Example calls

isort --diff --check --profile black myfile.py

isort --diff --check --profile black --settings-file .isort.cfg myfile.py

isort --profile black --settings-file .isort.cfg myfile.py

Help content

usage: isort [-h] [-V] [--vn] [-v] [--only-modified] [--dedup-headings] [-q]
             [-d] [--overwrite-in-place] [--show-config] [--show-files] [--df]
             [-c] [--ws] [--sp SETTINGS_PATH] [--cr CONFIG_ROOT]
             [--resolve-all-configs] [--profile PROFILE] [--old-finders]
             [-j [JOBS]] [--ac] [--interactive] [--format-error FORMAT_ERROR]
             [--format-success FORMAT_SUCCESS] [--srx] [--filter-files]
             [-s SKIP] [--extend-skip EXTEND_SKIP] [--sg SKIP_GLOB]
             [--extend-skip-glob EXTEND_SKIP_GLOB] [--gitignore]
             [--ext SUPPORTED_EXTENSIONS]
             [--blocked-extension BLOCKED_EXTENSIONS] [--dont-follow-links]
             [--filename FILENAME] [--allow-root] [-a ADD_IMPORTS] [--append]
             [--af] [--rm REMOVE_IMPORTS] [--float-to-top]
             [--dont-float-to-top] [--ca] [--cs] [-e] [--ff]
             [--fgw [FORCE_GRID_WRAP]] [-i INDENT]
             [--lbi LINES_BEFORE_IMPORTS] [--lai LINES_AFTER_IMPORTS]
             [--lbt LINES_BETWEEN_TYPES] [--le LINE_ENDING] [--ls] [--lss]
             [-m {GRID,VERTICAL,HANGING_INDENT,VERTICAL_HANGING_INDENT,VERTICAL_GRID,VERTICAL_GRID_GROUPED,VERTICAL_GRID_GROUPED_NO_COMMA,NOQA,VERTICAL_HANGING_INDENT_BRACKET,VERTICAL_PREFIX_FROM_MODULE_IMPORT,HANGING_INDENT_WITH_PARENTHESES,BACKSLASH_GRID,0,1,2,3,4,5,6,7,8,9,10,11}]
             [-n] [--nis] [--ot] [--dt] [--rr] [--reverse-sort]
             [--sort-order SORT_ORDER] [--sl] [--nsl SINGLE_LINE_EXCLUSIONS]
             [--tc] [--up] [-l LINE_LENGTH] [--wl WRAP_LENGTH]
             [--case-sensitive] [--remove-redundant-aliases] [--honor-noqa]
             [--treat-comment-as-code TREAT_COMMENTS_AS_CODE]
             [--treat-all-comment-as-code] [--formatter FORMATTER] [--color]
             [--ext-format EXT_FORMAT] [--star-first]
             [--split-on-trailing-comma] [--sd DEFAULT_SECTION]
             [--only-sections] [--ds] [--fas] [--fss] [--hcss] [--srss]
             [--fass] [-t FORCE_TO_TOP] [--combine-straight-imports]
             [--nlb NO_LINES_BEFORE] [--src SRC_PATHS]
             [-b KNOWN_STANDARD_LIBRARY]
             [--extra-builtin EXTRA_STANDARD_LIBRARY]
             [-f KNOWN_FUTURE_LIBRARY] [-o KNOWN_THIRD_PARTY]
             [-p KNOWN_FIRST_PARTY] [--known-local-folder KNOWN_LOCAL_FOLDER]
             [--virtual-env VIRTUAL_ENV] [--conda-env CONDA_ENV]
             [--py {all,2,27,3,310,311,312,313,314,36,37,38,39,auto}]
             [files ...]

Sort Python import definitions alphabetically within logical sections. Run
with no arguments to see a quick start guide, otherwise, one or more
files/directories/stdin must be provided. Use `-` as the first argument to
represent stdin. Use --interactive to use the pre 5.0.0 interactive behavior.
If you've used isort 4 but are new to isort 5, see the upgrading guide:
https://pycqa.github.io/isort/docs/upgrade_guides/5.0.0.html

general options:
  -h, --help            show this help message and exit
  -V, --version         Displays the currently installed version of isort.
  --vn, --version-number
                        Returns just the current version number without the
                        logo
  -v, --verbose         Shows verbose output, such as when files are skipped
                        or when a check is successful.
  --only-modified, --om
                        Suppresses verbose output for non-modified files.
  --dedup-headings      Tells isort to only show an identical custom import
                        heading comment once, even if there are multiple
                        sections with the comment set.
  -q, --quiet           Shows extra quiet output, only errors are outputted.
  -d, --stdout          Force resulting output to stdout, instead of in-place.
  --overwrite-in-place  Tells isort to overwrite in place using the same file
                        handle. Comes at a performance and memory usage
                        penalty over its standard approach but ensures all
                        file flags and modes stay unchanged.
  --show-config         See isort's determined config, as well as sources of
                        config options.
  --show-files          See the files isort will be run against with the
                        current config options.
  --df, --diff          Prints a diff of all the changes isort would make to a
                        file, instead of changing it in place
  -c, --check-only, --check
                        Checks the file for unsorted / unformatted imports and
                        prints them to the command line without modifying the
                        file. Returns 0 when nothing would change and returns
                        1 when the file would be reformatted.
  --ws, --ignore-whitespace
                        Tells isort to ignore whitespace differences when
                        --check-only is being used.
  --sp, --settings-path, --settings-file, --settings SETTINGS_PATH
                        Explicitly set the settings path or file instead of
                        auto determining based on file location.
  --cr, --config-root CONFIG_ROOT
                        Explicitly set the config root for resolving all
                        configs. When used with the --resolve-all-configs
                        flag, isort will look at all sub-folders in this
                        config root to resolve config files and sort files
                        based on the closest available config(if any)
  --resolve-all-configs
                        Tells isort to resolve the configs for all sub-
                        directories and sort files in terms of its closest
                        config files.
  --profile PROFILE     Base profile type to use for configuration. Profiles
                        include: black, django, pycharm, google, open_stack,
                        plone, attrs, hug, wemake, appnexus. As well as any
                        shared profiles.
  --old-finders, --magic-placement
                        Use the old deprecated finder logic that relies on
                        environment introspection magic.
  -j, --jobs [JOBS]     Number of files to process in parallel. Negative value
                        means use number of CPUs.
  --ac, --atomic        Ensures the output doesn't save if the resulting file
                        contains syntax errors.
  --interactive         Tells isort to apply changes interactively.
  --format-error FORMAT_ERROR
                        Override the format used to print errors.
  --format-success FORMAT_SUCCESS
                        Override the format used to print success.
  --srx, --sort-reexports
                        Automatically sort all re-exports (module level
                        __all__ collections)

target options:
  files                 One or more Python source files that need their
                        imports sorted.
  --filter-files        Tells isort to filter files even when they are
                        explicitly passed in as part of the CLI command.
  -s, --skip SKIP       Files that isort should skip over. If you want to skip
                        multiple files you should specify twice: --skip file1
                        --skip file2. Values can be file names, directory
                        names or file paths. To skip all files in a nested
                        path use --skip-glob.
  --extend-skip EXTEND_SKIP
                        Extends --skip to add additional files that isort
                        should skip over. If you want to skip multiple files
                        you should specify twice: --skip file1 --skip file2.
                        Values can be file names, directory names or file
                        paths. To skip all files in a nested path use --skip-
                        glob.
  --sg, --skip-glob SKIP_GLOB
                        Files that isort should skip over.
  --extend-skip-glob EXTEND_SKIP_GLOB
                        Additional files that isort should skip over
                        (extending --skip-glob).
  --gitignore, --skip-gitignore
                        Treat project as a git repository and ignore files
                        listed in .gitignore. NOTE: This requires git to be
                        installed and accessible from the same shell as isort.
  --ext, --extension, --supported-extension SUPPORTED_EXTENSIONS
                        Specifies what extensions isort can be run against.
  --blocked-extension BLOCKED_EXTENSIONS
                        Specifies what extensions isort can never be run
                        against.
  --dont-follow-links   Tells isort not to follow symlinks that are
                        encountered when running recursively.
  --filename FILENAME   Provide the filename associated with a stream.
  --allow-root          Tells isort not to treat / specially, allowing it to
                        be run against the root dir.

general output options:
  -a, --add-import ADD_IMPORTS
                        Adds the specified import line to all files,
                        automatically determining correct placement.
  --append, --append-only
                        Only adds the imports specified in --add-import if the
                        file contains existing imports.
  --af, --force-adds    Forces import adds even if the original file is empty.
  --rm, --remove-import REMOVE_IMPORTS
                        Removes the specified import from all files.
  --float-to-top        Causes all non-indented imports to float to the top of
                        the file having its imports sorted (immediately below
                        the top of file comment). This can be an excellent
                        shortcut for collecting imports every once in a while
                        when you place them in the middle of a file to avoid
                        context switching. *NOTE*: It currently doesn't work
                        with cimports and introduces some extra over-head and
                        a performance penalty.
  --dont-float-to-top   Forces --float-to-top setting off. See --float-to-top
                        for more information.
  --ca, --combine-as    Combines as imports on the same line.
  --cs, --combine-star  Ensures that if a star import is present, nothing else
                        is imported from that namespace.
  -e, --balanced        Balances wrapping to produce the most consistent line
                        length possible
  --ff, --from-first    Switches the typical ordering preference, showing from
                        imports first then straight ones.
  --fgw, --force-grid-wrap [FORCE_GRID_WRAP]
                        Force number of from imports (defaults to 2 when
                        passed as CLI flag without value) to be grid wrapped
                        regardless of line length. If 0 is passed in (the
                        global default) only line length is considered.
  -i, --indent INDENT   String to place for indents defaults to " " (4
                        spaces).
  --lbi, --lines-before-imports LINES_BEFORE_IMPORTS
  --lai, --lines-after-imports LINES_AFTER_IMPORTS
  --lbt, --lines-between-types LINES_BETWEEN_TYPES
  --le, --line-ending LINE_ENDING
                        Forces line endings to the specified value. If not
                        set, values will be guessed per-file.
  --ls, --length-sort   Sort imports by their string length.
  --lss, --length-sort-straight
                        Sort straight imports by their string length. Similar
                        to `length_sort` but applies only to straight imports
                        and doesn't affect from imports.
  -m, --multi-line {GRID,VERTICAL,HANGING_INDENT,VERTICAL_HANGING_INDENT,VERTICAL_GRID,VERTICAL_GRID_GROUPED,VERTICAL_GRID_GROUPED_NO_COMMA,NOQA,VERTICAL_HANGING_INDENT_BRACKET,VERTICAL_PREFIX_FROM_MODULE_IMPORT,HANGING_INDENT_WITH_PARENTHESES,BACKSLASH_GRID,0,1,2,3,4,5,6,7,8,9,10,11}
                        Multi line output (0-grid, 1-vertical, 2-hanging,
                        3-vert-hanging, 4-vert-grid, 5-vert-grid-grouped,
                        6-deprecated-alias-for-5, 7-noqa, 8-vertical-hanging-
                        indent-bracket, 9-vertical-prefix-from-module-import,
                        10-hanging-indent-with-parentheses).
  -n, --ensure-newline-before-comments
                        Inserts a blank line before a comment following an
                        import.
  --nis, --no-inline-sort
                        Leaves `from` imports with multiple imports 'as-is'
                        (e.g. `from foo import a, c ,b`).
  --ot, --order-by-type
                        Order imports by type, which is determined by case, in
                        addition to alphabetically. **NOTE**: type here refers
                        to the implied type from the import name
                        capitalization. isort does not do type introspection
                        for the imports. These "types" are simply:
                        CONSTANT_VARIABLE, CamelCaseClass,
                        variable_or_function. If your project follows PEP8 or
                        a related coding standard and has many imports this is
                        a good default, otherwise you likely will want to turn
                        it off. From the CLI the `--dont-order-by-type` option
                        will turn this off.
  --dt, --dont-order-by-type
                        Don't order imports by type, which is determined by
                        case, in addition to alphabetically. **NOTE**: type
                        here refers to the implied type from the import name
                        capitalization. isort does not do type introspection
                        for the imports. These "types" are simply:
                        CONSTANT_VARIABLE, CamelCaseClass,
                        variable_or_function. If your project follows PEP8 or
                        a related coding standard and has many imports this is
                        a good default. You can turn this on from the CLI
                        using `--order-by-type`.
  --rr, --reverse-relative
                        Reverse order of relative imports.
  --reverse-sort        Reverses the ordering of imports.
  --sort-order SORT_ORDER
                        Specify sorting function. Can be built in
                        (natural[default] = force numbers to be sequential,
                        native = Python's built-in sorted function) or an
                        installable plugin.
  --sl, --force-single-line-imports
                        Forces all from imports to appear on their own line
  --nsl, --single-line-exclusions SINGLE_LINE_EXCLUSIONS
                        One or more modules to exclude from the single line
                        rule.
  --tc, --trailing-comma
                        Includes a trailing comma on multi line imports that
                        include parentheses.
  --up, --use-parentheses
                        Use parentheses for line continuation on length limit
                        instead of slashes. **NOTE**: This is separate from
                        wrap modes, and only affects how individual lines that
                        are too long get continued, not sections of multiple
                        imports.
  -l, -w, --line-length, --line-width LINE_LENGTH
                        The max length of an import line (used for wrapping
                        long imports).
  --wl, --wrap-length WRAP_LENGTH
                        Specifies how long lines that are wrapped should be,
                        if not set line_length is used. NOTE: wrap_length must
                        be LOWER than or equal to line_length.
  --case-sensitive      Tells isort to include casing when sorting module
                        names
  --remove-redundant-aliases
                        Tells isort to remove redundant aliases from imports,
                        such as `import os as os`. This defaults to `False`
                        simply because some projects use these seemingly
                        useless aliases to signify intent and change
                        behaviour.
  --honor-noqa          Tells isort to honor noqa comments to enforce skipping
                        those comments.
  --treat-comment-as-code TREAT_COMMENTS_AS_CODE
                        Tells isort to treat the specified single line
                        comment(s) as if they are code.
  --treat-all-comment-as-code
                        Tells isort to treat all single line comments as if
                        they are code.
  --formatter FORMATTER
                        Specifies the name of a formatting plugin to use when
                        producing output.
  --color               Tells isort to use color in terminal output.
  --ext-format EXT_FORMAT
                        Tells isort to format the given files according to an
                        extensions formatting rules.
  --star-first          Forces star imports above others to avoid overriding
                        directly imported variables.
  --split-on-trailing-comma
                        Split imports list followed by a trailing comma into
                        VERTICAL_HANGING_INDENT mode

section output options:
  --sd, --section-default DEFAULT_SECTION
                        Sets the default section for import options:
                        ('FUTURE', 'STDLIB', 'THIRDPARTY', 'FIRSTPARTY',
                        'LOCALFOLDER')
  --only-sections, --os
                        Causes imports to be sorted based on their sections
                        like STDLIB, THIRDPARTY, etc. Within sections, the
                        imports are ordered by their import style and the
                        imports with the same style maintain their relative
                        positions.
  --ds, --no-sections   Put all imports into the same section bucket
  --fas, --force-alphabetical-sort
                        Force all imports to be sorted as a single section
  --fss, --force-sort-within-sections
                        Don't sort straight-style imports (like import sys)
                        before from-style imports (like from itertools import
                        groupby). Instead, sort the imports by module,
                        independent of import style.
  --hcss, --honor-case-in-force-sorted-sections
                        Honor `--case-sensitive` when `--force-sort-within-
                        sections` is being used. Without this option set,
                        `--order-by-type` decides module name ordering too.
  --srss, --sort-relative-in-force-sorted-sections
                        When using `--force-sort-within-sections`, sort
                        relative imports the same way as they are sorted when
                        not using that setting.
  --fass, --force-alphabetical-sort-within-sections
                        Force all imports to be sorted alphabetically within a
                        section
  -t, --top FORCE_TO_TOP
                        Force specific imports to the top of their appropriate
                        section.
  --combine-straight-imports, --csi
                        Combines all the bare straight imports of the same
                        section in a single line. Won't work with sections
                        which have 'as' imports
  --nlb, --no-lines-before NO_LINES_BEFORE
                        Sections which should not be split with previous by
                        empty lines
  --src, --src-path SRC_PATHS
                        Add an explicitly defined source path (modules within
                        src paths have their imports automatically categorized
                        as first_party). Glob expansion (`*` and `**`) is
                        supported for this option.
  -b, --builtin KNOWN_STANDARD_LIBRARY
                        Force isort to recognize a module as part of Python's
                        standard library.
  --extra-builtin EXTRA_STANDARD_LIBRARY
                        Extra modules to be included in the list of ones in
                        Python's standard library.
  -f, --future KNOWN_FUTURE_LIBRARY
                        Force isort to recognize a module as part of Python's
                        internal future compatibility libraries. WARNING: this
                        overrides the behavior of __future__ handling and
                        therefore can result in code that can't execute. If
                        you're looking to add dependencies such as six, a
                        better option is to create another section below
                        --future using custom sections. See:
                        https://github.com/PyCQA/isort#custom-sections-and-
                        ordering and the discussion here:
                        https://github.com/PyCQA/isort/issues/1463.
  -o, --thirdparty KNOWN_THIRD_PARTY
                        Force isort to recognize a module as being part of a
                        third party library.
  -p, --project KNOWN_FIRST_PARTY
                        Force isort to recognize a module as being part of the
                        current python project.
  --known-local-folder KNOWN_LOCAL_FOLDER
                        Force isort to recognize a module as being a local
                        folder. Generally, this is reserved for relative
                        imports (from . import module).
  --virtual-env VIRTUAL_ENV
                        Virtual environment to use for determining whether a
                        package is third-party
  --conda-env CONDA_ENV
                        Conda environment to use for determining whether a
                        package is third-party
  --py, --python-version {all,2,27,3,310,311,312,313,314,36,37,38,39,auto}
                        Tells isort to set the known standard library based on
                        the specified Python version. Default is to assume any
                        Python 3 version could be the target, and use a union
                        of all stdlib modules across versions. If auto is
                        specified, the version of the interpreter used to run
                        isort (currently: 313) will be used.

Installation on mega-linter Docker image

Dockerfile commands :

# renovate: datasource=pypi depName=black
ARG PIP_BLACK_VERSION=25.9.0
# renovate: datasource=pypi depName=isort
ARG PIP_ISORT_VERSION=7.0.0

PIP packages (Python):
- black==25.9.0
- isort==7.0.0

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