[lynda:course] Force log out (Closes #7361)

youtube_dl/extractor/lynda.py

@@ -82,6 +82,11 @@ def _login(self):
                         expected=True)
             raise ExtractorError('Unable to log in')
 
+    def _logout(self):
+        self._download_webpage(
+            'http://www.lynda.com/ajax/logout.aspx', None,
+            'Logging out', 'Unable to log out', fatal=False)
+
 
 class LyndaIE(LyndaBaseIE):
     IE_NAME = 'lynda'
@@ -210,6 +215,8 @@ def _real_extract(self, url):
             course_id, 'Downloading course JSON')
         course_json = json.loads(page)
 
+        self._logout()
+
         if 'Status' in course_json and course_json['Status'] == 'NotFound':
             raise ExtractorError(
                 'Course %s does not exist' % course_id, expected=True)