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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 validate(self, value: LocalizedValue, *_):
 """Validates that the values has been filled in for all required languages Exceptions are raises in order to notify the user of invalid values. Arguments: value: The value to validate. """


        if self.null:
            return

        for lang in self.required:
            lang_val = getattr(value, settings.LANGUAGE_CODE)

            if lang_val is None:
                raise IntegrityError('null value in column "%s.%s" violates '
                                     'not-null constraint' % (self.name, lang))