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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 verify_quote(self, quote_id, extra):
 """Verifies that a quote order is valid. :: extras = { 'hardware': {'hostname': 'test', 'domain': 'testing.com'}, 'quantity': 2 } manager = ordering.OrderingManager(env.client) result = manager.verify_quote(12345, extras) :param int quote_id: ID for the target quote :param dictionary extra: Overrides for the defaults of SoftLayer_Container_Product_Order :param int quantity: Quantity to override default """

        container = self.generate_order_template(quote_id, extra)
        clean_container = {}

        # There are a few fields that wil cause exceptions in the XML endpoing if you send in ''
        # reservedCapacityId and hostId specifically. But we clean all just to be safe.
        # This for some reason is only a problem on verify_quote.
        for key in container.keys():
            if container.get(key) != '':
                clean_container[key] = container[key]

        return self.client.call('SoftLayer_Billing_Order_Quote', 'verifyOrder', clean_container, id=quote_id)