public Optional<ArtifactDefinitions> getArtifactDefinitions() {
        return Optional.ofNullable(artifactDefinitions);
    }
Gets this TraceFile's Definitions.

@return an Optional Definitions container that contains this TraceFile's Definition
or isEmpty if Definition's has not been set.
smithy-codegen-core/src/main/java/software/amazon/smithy/codegen/core/trace/TraceFile.java