[dependencies] Create module with all dependency imports

yt_dlp/extractor/fc2.py

@@ -4,10 +4,10 @@ from .common import InfoExtractor
 from ..compat import (
     compat_parse_qs,
 )
+from ..dependencies import websockets
 from ..utils import (
     ExtractorError,
     WebSocketsWrapper,
-    has_websockets,
     js_to_json,
     sanitized_Request,
     std_headers,
@@ -170,7 +170,7 @@ class FC2LiveIE(InfoExtractor):
     }]
 
     def _real_extract(self, url):
-        if not has_websockets:
+        if not websockets:
             raise ExtractorError('websockets library is not available. Please install it.', expected=True)
         video_id = self._match_id(url)
         webpage = self._download_webpage('https://live.fc2.com/%s/' % video_id, video_id)

yt_dlp/extractor/twitcasting.py

@@ -2,7 +2,7 @@ import itertools
 import re
 
 from .common import InfoExtractor
-from ..downloader.websocket import has_websockets
+from ..dependencies import websockets
 from ..utils import (
     clean_html,
     ExtractorError,
@@ -161,7 +161,7 @@ class TwitCastingIE(InfoExtractor):
                     note='Downloading source quality m3u8',
                     headers=self._M3U8_HEADERS, fatal=False))
 
-            if has_websockets:
+            if websockets:
                 qq = qualities(['base', 'mobilesource', 'main'])
                 streams = traverse_obj(stream_server_data, ('llfmp4', 'streams')) or {}
                 for mode, ws_url in streams.items():