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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 get_object_context(root):
 """Depth-first discovery of authentication context for an object. Walks the ACL graph via ``__acl_bases__`` and merges the ``__acl_context__`` attributes. """


    context = {}
    for obj in iter_object_graph(root, parents_first=True):
        context.update(getattr(obj, '__acl_context__', {}))
    return context