Function not_node_ids 

pub fn not_node_ids(
    function: &str,
    param: &TraversalParam,
    graph: &str,
    id_type: &DataType,
    got: &str,
) -> String

“hop(seeds =>) must be node ids of graph ‘karate’, which are integers; got ‘a’”: a node-id argument that is not of the graph’s id type and does not cast to it. got is the offending value as SQL writes it, or its type.