two reasons for the 'to':

1) the token 'to' names the values in the result,

e.g. I end up with this in the expanded array of hashes:

  to => 'auckland',
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2) also, this is just an example, in reality there are more values, e.g.

  period => {
    20050824 => {
      to        => [ 'auckland', 'new york', ],
      transport => [ 'air', ]
    },
  },
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