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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(1) {
  ["query"]=>
  array(1) {
    ["namespaces"]=>
    array(18) {
      [-2]=>
      array(4) {
        ["id"]=>
        int(-2)
        ["case"]=>
        string(12) "first-letter"
        ["*"]=>
        string(5) "Media"
        ["canonical"]=>
        string(5) "Media"
      }
      [-1]=>
      array(4) {
        ["id"]=>
        int(-1)
        ["case"]=>
        string(12) "first-letter"
        ["*"]=>
        string(9) "Specjalna"
        ["canonical"]=>
        string(7) "Special"
      }
      [0]=>
      array(4) {
        ["id"]=>
        int(0)
        ["case"]=>
        string(12) "first-letter"
        ["*"]=>
        string(0) ""
        ["content"]=>
        string(0) ""
      }
      [1]=>
      array(5) {
        ["id"]=>
        int(1)
        ["case"]=>
        string(12) "first-letter"
        ["*"]=>
        string(8) "Dyskusja"
        ["subpages"]=>
        string(0) ""
        ["canonical"]=>
        string(4) "Talk"
      }
      [2]=>
      array(5) {
        ["id"]=>
        int(2)
        ["case"]=>
        string(12) "first-letter"
        ["*"]=>
        string(11) "Użytkownik"
        ["subpages"]=>
        string(0) ""
        ["canonical"]=>
        string(4) "User"
      }
      [3]=>
      array(5) {
        ["id"]=>
        int(3)
        ["case"]=>
        string(12) "first-letter"
        ["*"]=>
        string(21) "Dyskusja użytkownika"
        ["subpages"]=>
        string(0) ""
        ["canonical"]=>
        string(9) "User talk"
      }
      [4]=>
      array(5) {
        ["id"]=>
        int(4)
        ["case"]=>
        string(12) "first-letter"
        ["*"]=>
        string(3) "Lem"
        ["subpages"]=>
        string(0) ""
        ["canonical"]=>
        string(7) "Project"
      }
      [5]=>
      array(5) {
        ["id"]=>
        int(5)
        ["case"]=>
        string(12) "first-letter"
        ["*"]=>
        string(12) "Dyskusja Lem"
        ["subpages"]=>
        string(0) ""
        ["canonical"]=>
        string(12) "Project talk"
      }
      [6]=>
      array(4) {
        ["id"]=>
        int(6)
        ["case"]=>
        string(12) "first-letter"
        ["*"]=>
        string(4) "Plik"
        ["canonical"]=>
        string(4) "File"
      }
      [7]=>
      array(5) {
        ["id"]=>
        int(7)
        ["case"]=>
        string(12) "first-letter"
        ["*"]=>
        string(14) "Dyskusja pliku"
        ["subpages"]=>
        string(0) ""
        ["canonical"]=>
        string(9) "File talk"
      }
      [8]=>
      array(5) {
        ["id"]=>
        int(8)
        ["case"]=>
        string(12) "first-letter"
        ["*"]=>
        string(9) "MediaWiki"
        ["subpages"]=>
        string(0) ""
        ["canonical"]=>
        string(9) "MediaWiki"
      }
      [9]=>
      array(5) {
        ["id"]=>
        int(9)
        ["case"]=>
        string(12) "first-letter"
        ["*"]=>
        string(18) "Dyskusja MediaWiki"
        ["subpages"]=>
        string(0) ""
        ["canonical"]=>
        string(14) "MediaWiki talk"
      }
      [10]=>
      array(4) {
        ["id"]=>
        int(10)
        ["case"]=>
        string(12) "first-letter"
        ["*"]=>
        string(7) "Szablon"
        ["canonical"]=>
        string(8) "Template"
      }
      [11]=>
      array(5) {
        ["id"]=>
        int(11)
        ["case"]=>
        string(12) "first-letter"
        ["*"]=>
        string(17) "Dyskusja szablonu"
        ["subpages"]=>
        string(0) ""
        ["canonical"]=>
        string(13) "Template talk"
      }
      [12]=>
      array(5) {
        ["id"]=>
        int(12)
        ["case"]=>
        string(12) "first-letter"
        ["*"]=>
        string(5) "Pomoc"
        ["subpages"]=>
        string(0) ""
        ["canonical"]=>
        string(4) "Help"
      }
      [13]=>
      array(5) {
        ["id"]=>
        int(13)
        ["case"]=>
        string(12) "first-letter"
        ["*"]=>
        string(15) "Dyskusja pomocy"
        ["subpages"]=>
        string(0) ""
        ["canonical"]=>
        string(9) "Help talk"
      }
      [14]=>
      array(4) {
        ["id"]=>
        int(14)
        ["case"]=>
        string(12) "first-letter"
        ["*"]=>
        string(9) "Kategoria"
        ["canonical"]=>
        string(8) "Category"
      }
      [15]=>
      array(5) {
        ["id"]=>
        int(15)
        ["case"]=>
        string(12) "first-letter"
        ["*"]=>
        string(18) "Dyskusja kategorii"
        ["subpages"]=>
        string(0) ""
        ["canonical"]=>
        string(13) "Category talk"
      }
    }
  }
}