xxxxxxxxxx
# Pad a string on the left
"klueless-io".rjust(20)
# => " klueless-io"
"klueless-io".rjust(20, '-')
# => "---------klueless-io"
xxxxxxxxxx
# Pad a string on the right
"klueless-io".ljust(20)
# => "klueless-io "
"klueless-io".ljust(20, '-')
# => "klueless-io---------"