Function sources_to_model 

pub fn sources_to_model(
    sources: &[ModelSource],
    base_dir: &Path,
    verbose: u8,
) -> Result<Model>

Load all model sources and merge into single model.

• Sources may be a combination of files, directories, and urls.
• Model files may be .smithy or .json See the codegen.toml documentation on [[models]] for a description of valid ModelSources. If relative_dir is provided, all relative paths read will be made relative to that folder, (Relative paths in codegen.toml are relative to the file codegen.toml, not necessarily the current directory of the OS process) Returns single merged model.