Extracts ports ranges from the NSG rule object
            Returns an array of PortsRange tuples

def _get_rule_port_ranges(rule):
        """ Extracts ports ranges from the NSG rule object
            Returns an array of PortsRange tuples
        """
        properties = rule['properties']
        if 'destinationPortRange' in properties:
            return [PortsRangeHelper._get_port_range(properties['destinationPortRange'])]
        else:
            return [PortsRangeHelper._get_port_range(r)
                    for r in properties['destinationPortRanges']]