Pyyaml: Default dump behavior for inherited classes

Question

I have a class that inherits from one of the built-ins:

from yaml import YAMLObject, dump
class D(dict, YAMLObject):
   yaml_tag = u'!!map'
   ...

Is there a way to tell pyyaml that the dump of any instance of D should be treated like the parent (in this case dict)? I.e., I would like the following output:

d = {'a':1}
print( dump(d) )
>>> a: 1

Instead of

print( dump(D(d)) )
>>> !%21map {}

As you can see I already tried assigning the class a default tag, but that did not quite work out. Defining a custom dumper is unfortunately not an option.

Answer 1

Short addition: Converting the data back to a dict first before dumping it is another elegant solution I completely missed:

d = D({'a':1})
print( dump(dict(d)) )
>>> a: 1