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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 modelrepr(instance) -> str: """ Default ``repr`` version of a Django model object, for debugging. """

    elements = []
    # noinspection PyProtectedMember
    for f in instance._meta.get_fields():
        # https://docs.djangoproject.com/en/2.0/ref/models/meta/
        if f.auto_created:
            continue
        if f.is_relation and f.related_model is None:
            continue
        fieldname = f.name
        try:
            value = repr(getattr(instance, fieldname))
        except ObjectDoesNotExist:
            value = "<RelatedObjectDoesNotExist>"
        elements.append("{}={}".format(fieldname, value))
    return "<{} <{}>>".format(type(instance).__name__,
                              ", ".join(elements))