Add function add_default_info_extractors to YoutubeDL

It adds to the list the ies returned by ge_extractors

youtube_dl/YoutubeDL.py

@@ -13,7 +13,7 @@ import time
 import traceback
 
 from .utils import *
-from .extractor import get_info_extractor
+from .extractor import get_info_extractor, gen_extractors
 from .FileDownloader import FileDownloader
 
 
@@ -113,6 +113,13 @@ class YoutubeDL(object):
         self._ies.append(ie)
         ie.set_downloader(self)
 
+    def add_default_info_extractors(self):
+        """
+        Add the InfoExtractors returned by gen_extractors to the end of the list
+        """
+        for ie in gen_extractors():
+            self.add_info_extractor(ie)
+
     def add_post_processor(self, pp):
         """Add a PostProcessor object to the end of the chain."""
         self._pps.append(pp)