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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 as_dict(self, keep_readonly=True, key_transformer=attribute_transformer):
 """Return a dict that can be JSONify using json.dump. Advanced usage might optionaly use a callback as parameter: .. code::python def my_key_transformer(key, attr_desc, value):
 return key Key is the attribute name used in Python. Attr_desc is a dict of metadata. Currently contains 'type' with the msrest type and 'key' with the RestAPI encoded key. Value is the current value in this object. The string returned will be used to serialize the key. If the return type is a list, this is considered hierarchical result dict. See the three examples in this file: - attribute_transformer - full_restapi_key_transformer - last_restapi_key_transformer :param function key_transformer: A key transformer function. :returns: A dict JSON compatible object :rtype: dict """

        serializer = Serializer(self._infer_class_models())
        return serializer._serialize(self, key_transformer=key_transformer, keep_readonly=keep_readonly)