What is this about?

About justifying so called f-strings.

TLDR

some_text = "foobar"
how_much = 10
print(f"{some_text:<{how_much}}\tSome description")

Example

max_name_len = max(len(p.name) for p in prompts)  
while prompt not in prompts:  
    click.echo("Choose one of the following prompts:\n")  
    for p in prompts:  
        line = f"{p.name:<{max_name_len}}\t{p.description}"  
        click.echo(line)  
    click.echo()