Function write_graphml 

pub fn write_graphml<W: Write>(
    writer: &mut W,
    nodes: &[Node],
    edges: &[Edge],
) -> Result<(), ExportError>

Writes a complete GraphML document to the given writer.

Node labels are stored as a _labels data key, edge types as _type. Node IDs are prefixed with n, edge IDs with e (GraphML convention).

Errors

Returns ExportError::Io if writing fails.