code: def GetBuilder(self, context, fleetspeak_service_config):
      
      try:
        if "Target:Darwin" in context:
          return builders.DarwinClientBuilder(
              context=context,
              fleetspeak_service_config=fleetspeak_service_config)
        elif "Target:Windows" in context:
          return builders.WindowsClientBuilder(context=context)
        elif "Target:LinuxDeb" in context:
          return builders.LinuxClientBuilder(context=context)
        elif "Target:LinuxRpm" in context:
          return builders.CentosClientBuilder(context=context)
        else:
          parser.error("Bad build context: %s" % context)
      except AttributeError:
        raise RuntimeError("Unable to build for platform %s when running "
                           "on current platform." % self.platform)
docs: Get instance of builder class based on flags.