protected void setIamCredentials(AWSCredentialsProvider iamCredentials) {
        this.iamCredentials = iamCredentials;
    }
Base class for all Open SDK client builders.

@param <Subclass>    Concrete builder for better fluent setters.
@param <TypeToBuild> Type being built by concrete builder.
aws-java-sdk-opensdk/src/main/java/com/amazonaws/opensdk/protect/client/SdkSyncClientBuilder.java