+ selection.add_option(
+ '--match-filter',
+ metavar='FILTER', dest='match_filter', default=None,
+ help=(
+ 'Generic video filter (experimental). '
+ 'Specify any key (see help for -o for a list of available keys) to'
+ ' match if the key is present, '
+ '!key to check if the key is not present,'
+ 'key > NUMBER (like "comment_count > 12", also works with '
+ '>=, <, <=, !=, =) to compare against a number, and '
+ '& to require multiple matches. '
+ 'Values which are not known are excluded unless you'
+ ' put a question mark (?) after the operator.'
+ 'For example, to only match videos that have been liked more than '
+ '100 times and disliked less than 50 times (or the dislike '
+ 'functionality is not available at the given service), but who '
+ 'also have a description, use --match-filter '
+ '"like_count > 100 & dislike_count <? 50 & description" .'
+ ))