Im trying to clone a hash, to make a new copy of the original hash but it seems that when I set a value in the new hash, I have the same effect on the original hash. 

```
rr = Hash.new
command = "/usr/local/bin/aws route53 list-resource-record-sets --hosted-zone-id EXAMPLEID --max-items 1"

rr=JSON.parse(%x{#{command}})

puts rr

if rr["ResourceRecordSets"][0]["TTL"] != 60
  new_rr = rr.clone
  new_rr["ResourceRecordSets"][0]["TTL"] = 60
  puts rr
  puts new_rr
end

```

Output: 

```
{"NextRecordType"=>"MX", "NextRecordName"=>"example.com.", "ResourceRecordSets"=>[{"ResourceRecords"=>[{"Value"=>"1.2.3.4"}], "Type"=>"A", "Name"=>"example.com.", "TTL"=>1800}], "MaxItems"=>"1", "IsTruncated"=>true}
{"NextRecordType"=>"MX", "NextRecordName"=>"example.com.", "ResourceRecordSets"=>[{"ResourceRecords"=>[{"Value"=>"1.2.3.4"}], "Type"=>"A", "Name"=>"example.com.", "TTL"=>60}], "MaxItems"=>"1", "IsTruncated"=>true}
{"NextRecordType"=>"MX", "NextRecordName"=>"example.com.", "ResourceRecordSets"=>[{"ResourceRecords"=>[{"Value"=>"1.2.3.4"}], "Type"=>"A", "Name"=>"example.com.", "TTL"=>60}], "MaxItems"=>"1", "IsTruncated"=>true}

```

I dont see Hash.clone documented in Ruby 2.0, should I be using another method to create a Hash copy now? 

Thanks in advance.