code: def load_plugins(builtin=True, others=True):
      
      for entry_point in pkg_resources.iter_entry_points('yolk.plugins'):
          #LOG.debug("load plugin %s" % entry_point)
          try:
              plugin = entry_point.load()
          except KeyboardInterrupt:
              raise
          except Exception as err_msg:
              # never want a plugin load to exit yolk
              # but we can't log here because the logger is not yet
              # configured
              warn("Unable to load plugin %s: %s" % \
                      (entry_point, err_msg), RuntimeWarning)
              continue
          if plugin.__module__.startswith('yolk.plugins'):
              if builtin:
                  yield plugin
          elif others:
              yield plugin
docs: Load plugins, either builtin, others, or both.