# dokumentasi Django 2.0.8

# Kode sumber untuk django.core.checks.messages

    # Levels
    DEBUG = 10
    INFO = 20
    WARNING = 30
    ERROR = 40
    CRITICAL = 50

    class CheckMessage:

        def __init__(self, level, msg, hint=None, obj=None, id=None):
            assert isinstance(level, int), "The first argument should be level."
            self.level = level
            self.msg = msg
            self.hint = hint
            self.obj = obj
            self.id = id

        def __eq__(self, other):
            return (
                isinstance(other, self.__class__) and
                all(getattr(self, attr) == getattr(other, attr)
                    for attr in ['level', 'msg', 'hint', 'obj', 'id'])
            )

        def __str__(self):
            from django.db import models

            if self.obj is None:
                obj = "?"
            elif isinstance(self.obj, models.base.ModelBase):
                # We need to hardcode ModelBase and Field cases because its __str__
                # method doesn't return "applabel.modellabel" and cannot be changed.
                obj = self.obj._meta.label
            else:
                obj = str(self.obj)
            id = "(%s) " % self.id if self.id else ""
            hint = "\n\tHINT: %s" % self.hint if self.hint else ''
            return "%s: %s%s%s" % (obj, id, self.msg, hint)

        def __repr__(self):
            return "<%s: level=%r, msg=%r, hint=%r, obj=%r, id=%r>" % \
                (self.__class__.__name__, self.level, self.msg, self.hint, self.obj, self.id)

        def is_serious(self, level=ERROR):
            return self.level >= level

        def is_silenced(self):
            from django.conf import settings
            return self.id in settings.SILENCED_SYSTEM_CHECKS

    class Debug(CheckMessage):
        def __init__(self, *args, **kwargs):
            super().__init__(DEBUG, *args, **kwargs)

    class Info(CheckMessage):
        def __init__(self, *args, **kwargs):
            super().__init__(INFO, *args, **kwargs)

    class Warning(CheckMessage):
        def __init__(self, *args, **kwargs):
            super().__init__(WARNING, *args, **kwargs)

    class Error(CheckMessage):
        def __init__(self, *args, **kwargs):
            super().__init__(ERROR, *args, **kwargs)

    class Critical(CheckMessage):
        def __init__(self, *args, **kwargs):
            super().__init__(CRITICAL, *args, **kwargs)