Original code copyright (C) 2009-2022 Rudolf Cardinal (

This file is part of cardinal_pythonlib.

Licensed under the Apache License, Version 2.0 (the “License”); you may not use this file except in compliance with the License. You may obtain a copy of the License at

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Helper functions for Django fields.

cardinal_pythonlib.django.fields.helpers.choice_explanation(value: str, choices: Iterable[Tuple[str, str]]) str[source]

Returns the explanation associated with a Django choice tuple-list.

cardinal_pythonlib.django.fields.helpers.valid_choice(strvalue: str, choices: Iterable[Tuple[str, str]]) bool[source]

Checks that value is one of the valid option in choices, where choices is a list/tuple of 2-tuples (option, description).

Note that parameters sent by URLconf are always strings ( but Python is happy with a string-to-integer-PK lookup, e.g.

Study.objects.get(pk="1")  # also works

Choices can be non-string, though, so we compare against a string version of the choice.