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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 get_conditions(self, service_id):
 """ Build a Conditions XML block for a SAML 1.1 Assertion. """

        conditions = etree.Element('Conditions')
        conditions.set('NotBefore', self.instant())
        conditions.set('NotOnOrAfter', self.instant(offset=30))
        restriction = etree.SubElement(conditions, 'AudienceRestrictionCondition')
        audience = etree.SubElement(restriction, 'Audience')
        audience.text = service_id
        return conditions