public static Attachment fromBase64( String base64encodedContent, MediaType mediaType ) {
        if( !mediaType.isBinary() ) {
            throw new IllegalArgumentException( "MediaType must be binary" );
        }
        return new Attachment( base64encodedContent, mediaType );
    }
Equivalent to {@link com.tngtech.jgiven.attachment.Attachment#Attachment(String, MediaType)}
@throws java.lang.IllegalArgumentException if mediaType is not binary
jgiven-core/src/main/java/com/tngtech/jgiven/attachment/Attachment.java