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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_list(self, value):
 """ Validate data before saving to database. Arguemtns: value(list):
 list to be validated Returns: list if validation is successful Raises: ValidationError """

        if len(value) > self.max_items:
            raise ValidationError(
                u'list must not contain more than {max_items} items.'.format(max_items=self.max_items)
            )

        if all(isinstance(item, six.string_types) for item in value) is False:
            raise ValidationError(u'list must only contain strings.')

        return value