Where is localization stored in wordpress?

Question

WordPress

comments_popup_link( esc_html__( 'Leave a comment', 'tsumugi' ), esc_html__( '1 Comment', 'tsumugi' ), esc_html__( '% Comments', 'tsumugi' ) );

There is such a line, but the site does not display Leave a comment, but "leave a comment", and so on.
In which file is localization stored?

Answer 1

If you read the documentation, you would immediately understand that localization is stored in the tsumugi theme , or plugin, in the languages ​​folder.