The P2P classes for the Python test suite do not behave as the Core node does with respect to sending a version message: The expected behavior is for a node to send a version message as his first message provided he is the connection initiator, or respond with a version message upon receiving one is he is the responder. However, the various P2P nodes under the test framework eagerly send a version message as soon as a connection is made, indistinguishable of whether they are the initiators or not. This PR addresses that.
on_version behavior is overwritten from the parent classes, but it is really not needed. The classes are really just an alias of the parent class, probably to give it a more expressive name so they’re purpose is easily identifiable on the tests, but which behavior is nor really different.
on_version redefinition can simply be dropped.p2p_connected_to_node uses (and, therefore, how it is described in add_p2p_connection and add_outbound_p2p_connection). This is due to the docs in the aforementioned methods describe the connection from the POV of the TestedNode (i.e. the Core node being tested) while the new comments do so from the python node.