Function ZL_Compressor_getGraph 

pub unsafe extern "C" fn ZL_Compressor_getGraph(
    compressor: *const ZL_Compressor,
    graph: *const c_char,
) -> ZL_GraphID

@brief Lookup a graph by name.

Looks up a graph with the given name and returns it. Anchor graphs (graphs whose name starts with ‘!’) can be looked up by name, excluding the leading ‘!’. Standard graphs can also be looked up by name. Non-anchor graphs are assigned a unique name by suffixing them with #${unique}. They can be looked up if you know the unique name.

@returns The graph if it exists, or ZL_GRAPH_ILLEGAL.