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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def check_fieldsets(*args, **kwargs):
 """ A Django system check to make sure that, if defined, CONFIG_FIELDSETS accounts for every entry in settings.CONFIG. """

    if hasattr(settings, "CONFIG_FIELDSETS") and settings.CONFIG_FIELDSETS:
        inconsistent_fieldnames = get_inconsistent_fieldnames()
        if inconsistent_fieldnames:
            return [
                checks.Warning(
                    _(
                        "CONSTANCE_CONFIG_FIELDSETS is missing "
                        "field(s) that exists in CONSTANCE_CONFIG."
                    ),
                    hint=", ".join(sorted(inconsistent_fieldnames)),
                    obj="settings.CONSTANCE_CONFIG",
                    id="constance.E001",
                )
            ]
    return []