Man pages matching name pcre2_serialize_get_number_of_codes in section 3:

pcre2_serialize_get_number_of_codes.3.en	debian 10 / libpcre2-dev
pcre2_serialize_get_number_of_codes.3.en	debian 11 / libpcre2-dev
pcre2_serialize_get_number_of_codes.3.en	debian 12 / libpcre2-dev