syntax_data: {"ast_node_type":"other","tokens":[{"end":58,"kind":"keyword","start":0,"text":"///"}]}
source_snippet: /// selected, and `source_args` is its generic parameters.
context_before: /// type parameters of the two impls. Here the `source_impl` is the one we've
context_after: /// And `target_node` is the impl/trait we're actually going to get the