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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 _val_is_unique(val, field):
 """ Currently only checks the field's uniqueness, not the model validation. """

        if val is None:
            return False

        if not field.unique:
            return True

        field_name = field.name
        return field.model.objects.filter(**{field_name: val}).count() == 0