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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 _red_listing_validation(key, listing):
 """ Raises an RedValidationError, if the given listing does not comply with cwl_job_listing_schema. If listing is None or an empty list, no exception is thrown. :param key: The input key to build an error message if needed. :param listing: The listing to validate :raise RedValidationError: If the given listing does not comply with cwl_job_listing_schema """


    if listing:
        try:
            jsonschema.validate(listing, cwl_job_listing_schema)
        except ValidationError as e:
            raise RedValidationError('REDFILE listing of input "{}" does not comply with jsonschema: {}'
                                     .format(key, e.context))