ShippingLabel

Common errors

• ModuleNotFoundError: No module named 'shippinglabel.dependencies'

  cause The `shippinglabel.dependencies` submodule was removed in version 2.0.0.
  fix Update your import statements and code to use `shippinglabel.requirements` or `packaging` for dependency-related functionality.

• SyntaxError: invalid syntax (on Python 3.6)

  cause Attempting to run `shippinglabel` version 2.0.0 or higher on an unsupported Python 3.6 environment.
  fix Upgrade your Python interpreter to 3.7 or a later supported version.

• AttributeError: module 'shippinglabel' has no attribute 'entry_points'

  cause The `shippinglabel.entry_points` module was removed in version 2.0.0.
  fix Refactor code to use `importlib.metadata` or the `entrypoints` library directly for entry point discovery.

Warnings

• breaking Version 2.0.0 dropped support for Python 3.6. Users on Python 3.6 will encounter `ImportError` or `SyntaxError`.
  Fix: Upgrade your Python interpreter to 3.7 or a later supported version.
• breaking The `shippinglabel.dependencies` module was entirely removed in 2.0.0.
  Fix: Migrate usage to `shippinglabel.requirements` for requirement parsing or use the `packaging` library directly for PEP 508 parsing.
• breaking The `shippinglabel.entry_points` module was entirely removed in 2.0.0.
  Fix: Refactor code to use standard `importlib.metadata` (Python 3.8+) or `entrypoints` library for entry point discovery.
• gotcha While `trove-classifiers` is a declared dependency, `shippinglabel` includes a vendored copy. If you explicitly install a different version of `trove-classifiers`, `shippinglabel` will use that instead, potentially leading to inconsistencies if there are API changes.
  Fix: To ensure consistent classifier validation, rely on `shippinglabel`'s bundled `trove-classifiers` or explicitly install and manage the `trove-classifiers` version if you have it as a direct dependency in other parts of your project.

Install

• pip install shippinglabel Install with pip

Imports

• get_valid_classifiers

  from shippinglabel.classifiers import get_valid_classifiers

  Function to retrieve a set of valid PyPI classifiers.
• parse_requirements

  from shippinglabel.requirements import parse_requirements

  Function to parse Python project requirements from strings or files.
• checksum_package

  from shippinglabel.checksum import checksum_package

  Function to calculate a package's checksum.

Quickstart

This quickstart demonstrates how to use the `shippinglabel.classifiers` module to programmatically retrieve and validate PyPI classifiers. It fetches the complete set of valid classifiers and checks for the presence of specific ones.

from shippinglabel.classifiers import get_valid_classifiers

# Get all valid PyPI classifiers as a frozenset
classifiers = get_valid_classifiers()
print(f"Total valid classifiers: {len(classifiers)}")

# Check if a specific classifier is valid
is_python3_only_valid = "Programming Language :: Python :: 3 :: Only" in classifiers
print(f"'Programming Language :: Python :: 3 :: Only' is valid: {is_python3_only_valid}")

is_non_existent_valid = "Operating System :: Brainfuck" in classifiers
print(f"'Operating System :: Brainfuck' is valid: {is_non_existent_valid}")