Remove unused variable

wagtailvideos/models.py

@@ -171,11 +171,11 @@ class AbstractVideo(CollectionMember, index.Indexed, models.Model):
     @property
     def file_ext(self):
         return os.path.splitext(self.filename())[1][1:]
-    
+
     @property
     def content_type(self):
         mime = mimetypes.MimeTypes()
-        mimetype = mime.guess_type(self.url)[0] or mime.guess_type(self.filename())[0]
+        return mime.guess_type(self.url)[0] or mime.guess_type(self.filename())[0]
 
     def is_editable_by_user(self, user):
         from wagtailvideos.permissions import permission_policy
@@ -202,7 +202,6 @@ class AbstractVideo(CollectionMember, index.Indexed, models.Model):
         for transcode in transcodes:
             sources.append("<source src='{0}' type='video/{1}' >".format(transcode.url, transcode.media_format.name))
 
-        mime = mimetypes.MimeTypes()
         sources.append("<source src='{0}' type='{1}'>"
                        .format(self.url, self.content_type))