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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_string(string, options=None):
 """Validate the input `string` according to the options passed in. If any exceptions are raised during validation, no further validation will take place. Args: string: The string containing the JSON to be validated. options: An instance of ``ValidationOptions``. Returns: An ObjectValidationResults instance, or a list of such. """

    output.info("Performing JSON schema validation on input string: " + string)
    stream = io.StringIO(string)
    return validate(stream, options)