Encoding nested python object in JSON

I want to encode objects in JSON. But, I can not figure out how to make the output without the string escaping.

import json
 
 class Abc:
     def __init__(self):
         self.name="abc name"
     def toJSON(self):
         return json.dumps(self.__dict__, cls=ComplexEncoder)
 
 class Doc:
     def __init__(self):
         self.abc=Abc()
     def toJSON(self):
         return json.dumps(self.__dict__, cls=ComplexEncoder)
 
 class ComplexEncoder(json.JSONEncoder):
     def default(self, obj):
         if isinstance(obj, Abc) or isinstance(obj, Doc):
             return obj.toJSON()
         else:
             return json.JSONEncoder.default(self, obj)
 
 doc=Doc()
 print doc.toJSON()
 

The result is (the dumps returns a string representation, that's why the " are escaped)

{"abc": "{\"name\": \"abc name\"}"}
 

I want something a little bit different. The expected result is

{"abc": {"name": "abc name"}"}
 

But I don't see how to...
Any hint ?

thanks in advance.

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