One of the exercises in this chapter requires the Poppler package (PDF utils) to be installed; it can be installed as follows:
On Ubuntu: sudo apt install poppler-utils
On Fedora: sudo dnf install poppler-utils-<version#>
Regarding the Fedora case: to get the version number, just type the above command, and after typing poppler-utils- press the Tab key twice; it will autocomplete providing a list of choices. Choose the latest version and press Enter.