hash map of hash keys in ruby

hashmap.rb

irb(main):205:0> a
{{1 => 5} => 2}
irb(main):206:0> a.put ( Hamster.hash (3 => 3) , 3)
SyntaxError: (irb):206: syntax error, unexpected tASSOC, expecting ')'
a.put ( Hamster.hash (3 => 3) , 3)
                          ^
	from /usr/bin/irb:12:in `<main>'

a.put { Hamster.hash (3 => 3) , 3}
SyntaxError: (irb):207: syntax error, unexpected tASSOC, expecting ')'
a.put { Hamster.hash (3 => 3) , 3}
                          ^
	from /usr/bin/irb:12:in `<main>'

a.put Hamster.hash(3 => 3), 3
{{1 => 5} => 2, {3 => 3} => 3}