FiftyOne Code Style Skill

FiftyOne Code Style

Module Template

"""
Module description.

| Copyright 2017-2026, Voxel51, Inc.
| `voxel51.com <https://voxel51.com/>`_
|
"""
import logging
import os

import numpy as np

import eta.core.utils as etau

import fiftyone as fo
import fiftyone.core.fields as fof
import fiftyone.core.labels as fol
import fiftyone.core.utils as fou

logger = logging.getLogger(__name__)


def public_function(arg):
    """Public API function."""
    return _helper(arg)


def _helper(arg):
    """Private helper."""
    return arg

Import Organization

Four groups, alphabetized within each, separated by blank lines:

| Group | Example | |-------|---------| | 1. Standard library | import logging, import os | | 2. Third-party | import numpy as np | | 3. eta packages | import eta.core.utils as etau | | 4. FiftyOne | import fiftyone.core.labels as fol |

FiftyOne Import Aliases

| Module | Alias | |--------|-------| | fiftyone | fo | | fiftyone.core.labels | fol | | fiftyone.core.fields | fof | | fiftyone.core.media | fom | | fiftyone.core.storage | fos | | fiftyone.core.utils | fou | | fiftyone.utils.image | foui | | fiftyone.utils.video | fouv |

Docstrings (Google-Style)

def get_operator(operator_uri, enabled=True):
    """Gets the operator with the given URI.

    Args:
        operator_uri: the operator URI
        enabled (True): whether to include only enabled operators (True) or
            only disabled operators (False) or all operators ("all")

    Returns:
        an :class:`fiftyone.operators.Operator`

    Raises:
        ValueError: if the operator is not found
    """

Key patterns:

Args with defaults: param (default): description
Multi-line descriptions: indent continuation
Cross-references: :class:fiftyone.module.Class``

Lazy Imports

Use fou.lazy_import() for optional/heavy dependencies:

o3d = fou.lazy_import("open3d", callback=lambda: fou.ensure_package("open3d"))

mask_utils = fou.lazy_import(
    "pycocotools.mask", callback=lambda: fou.ensure_import("pycocotools")
)

Guard Patterns

Use hasattr() for optional attributes:

if hasattr(label, "confidence"):
    if label.confidence is None or label.confidence < threshold:
        label = label.__class__()

Error Handling

Use logger.warning() for non-fatal errors:

try:
    result = process_data(data)
except Exception as e:
    logger.warning("Failed to process data: %s", e)

Avoid Redundant Code

Before writing new functions, search for existing implementations:

Local: search the FiftyOne source if available in the environment
Remote: search https://github.com/voxel51/fiftyone
Check fiftyone/core/utils.py and fiftyone/utils/* first

Common Utilities

| Module | Functions | |--------|-----------| | fou | lazy_import(), ensure_package(), extract_kwargs_for_class() | | etau | guess_mime_type(), ensure_dir(), make_temp_dir() |

Quick Reference

| Pattern | Convention | |---------|------------| | Module structure | Docstring → imports → logger → public → private | | Private functions | _prefix | | Docstrings | Google-style with Args/Returns/Raises | | Error handling | logger.warning() for non-fatal | | Lazy imports | fou.lazy_import() for optional deps | | Guard patterns | hasattr() checks | | Import aliases | fo, fol, fof, fom, fos, fou |

Agent Skills: FiftyOne Code Style

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