docs: protected static Platform getDefaultPlatform(){
          // attempt to get assigned platform identifier from the environment variables
          String envPlatformId = System.getenv("PI4J_PLATFORM");
  
          // attempt to get assigned platform identifier from the system properties
          String platformId = System.getProperty("pi4j.platform", envPlatformId);
  
          // if a platform id was found in the system properties, then
          // attempt to lookup the platform enumeration using the platform
          // identifier string.  If found then return the platform enum.
          if(platformId != null && !platformId.isEmpty()){
              Platform pltfrm = Platform.fromId(platformId);
              if(pltfrm != null){
                  return pltfrm;
              }
          }
  
          // the RASPBERRY_PI is the default platform;
          // (... in time perhaps some auto-platform detection could be implemented here ...)
          return Platform.RASPBERRYPI;
      }