code: def joint(node):
    
    node, _, _ = _fix(node)
    body = node.body[0].body[:-1] + node.body[1].body
    func = gast.Module(body=[gast.FunctionDef(
        name=node.body[0].name, args=node.body[1].args, body=body,
        decorator_list=[], returns=None)])
    # Clean up
    anno.clearanno(func)
    return func
docs: Merge the bodies of primal and adjoint into a single function.
  
    Args:
      node: A module with the primal and adjoint function definitions as returned
          by `reverse_ad`.
  
    Returns:
      func: A `Module` node with a single function definition containing the
          combined primal and adjoint.