You are looking at the HTML representation of the DUMP format.
HTML is good for debugging, but is unsuitable for application use.
Specify the format parameter to change the output format.
To see the non HTML representation of the DUMP format, set format=dump.
See the complete documentation, or API help for more information.
array(2) {
  ["warnings"]=>
  array(1) {
    ["dumpfm"]=>
    array(1) {
      ["*"]=>
      string(68) "format=dumpfm has been deprecated. Please use format=jsonfm instead."
    }
  }
  ["query"]=>
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    ["namespaces"]=>
    array(18) {
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        ["id"]=>
        int(-2)
        ["case"]=>
        string(12) "first-letter"
        ["*"]=>
        string(5) "Media"
        ["canonical"]=>
        string(5) "Media"
      }
      [-1]=>
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        ["id"]=>
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        string(12) "first-letter"
        ["*"]=>
        string(8) "Speciale"
        ["canonical"]=>
        string(7) "Special"
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        ["id"]=>
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        ["*"]=>
        string(0) ""
        ["content"]=>
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        int(1)
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        string(12) "first-letter"
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        ["subpages"]=>
        string(0) ""
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        ["canonical"]=>
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        string(12) "first-letter"
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        ["id"]=>
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        ["canonical"]=>
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      }
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        ["case"]=>
        string(12) "first-letter"
        ["*"]=>
        string(9) "Categoria"
        ["canonical"]=>
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      }
      [15]=>
      array(5) {
        ["id"]=>
        int(15)
        ["case"]=>
        string(12) "first-letter"
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        ["subpages"]=>
        string(0) ""
        ["canonical"]=>
        string(13) "Category talk"
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}