makes a new, empty, anonymous array for you, installs it into
C<%table>, and then pushes C<Athens> onto it. This is called
'autovivification'--bringing things to life automatically. Perl saw
-that they key wasn't in the hash, so it created a new hash entry
+that the key wasn't in the hash, so it created a new hash entry
automatically. Perl saw that you wanted to use the hash value as an
array, so it created a new empty array and installed a reference to it
in the hash automatically. And as usual, Perl made the array one