Copyright (c) 2026 Oliver Haas
Portions Copyright (c) Praekelt Foundation and individual contributors

This software is a derivative work of django-dirtyfields, originally
created by the Praekelt Foundation and subsequently maintained by
Romain Garrigues and contributors at
https://github.com/romgar/django-dirtyfields. The "dirty fields"
concept, the original public API surface (DirtyFieldsMixin, the
is_dirty / get_dirty_fields / save_dirty_fields methods, the
ENABLE_M2M_CHECK / FIELDS_TO_CHECK / compare_function configuration
hooks), the regression test scenarios in tests/test_non_regression.py,
the timezone-aware comparison helpers, and large portions of the
documentation and structure all derive from that project. Sincere
thanks to the original authors and the upstream contributors — this
fork would not exist without their work.

The implementation has since been substantially rewritten around a
Cython-compiled descriptor approach (replacing upstream's signal-based
post_init snapshot), but the contract and intent remain those of the
original.

All rights reserved.

Redistribution and use in source and binary forms, with or without
modification, are permitted provided that the following conditions are
met:

    1.  Redistributions of source code must retain the above copyright
        notice, this list of conditions and the following disclaimer.

    2.  Redistributions in binary form must reproduce the above
        copyright notice, this list of conditions and the following
        disclaimer in the documentation and/or other materials provided
        with the distribution.

    3.  Neither the name of the copyright holders nor the names of
        their contributors may be used to endorse or promote products
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"AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
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