$ sudo grep -R "Package: u-boot-tools" /var/lib/apt/lists/ 

/var/lib/apt/lists/archive.ubuntu.com_ubuntu_dists_rusty_main_i18n_Translation-en:Package: u-boot-tools

/var/lib/apt/lists/archive.ubuntu.com_ubuntu_dists_trusty_main_binary-amd64_Packages:Package: u-boot-tools