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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 JSON format, set format=json.
See the complete documentation, or API help for more information.
{
    "query": {
        "namespaces": {
            "-2": {
                "id": -2,
                "case": "first-letter",
                "*": "Media",
                "canonical": "Media"
            },
            "-1": {
                "id": -1,
                "case": "first-letter",
                "*": "Specjalna",
                "canonical": "Special"
            },
            "0": {
                "id": 0,
                "case": "first-letter",
                "*": "",
                "content": ""
            },
            "1": {
                "id": 1,
                "case": "first-letter",
                "*": "Dyskusja",
                "subpages": "",
                "canonical": "Talk"
            },
            "2": {
                "id": 2,
                "case": "first-letter",
                "*": "Archiwista",
                "subpages": "",
                "canonical": "User"
            },
            "3": {
                "id": 3,
                "case": "first-letter",
                "*": "Dyskusja Archiwisty",
                "subpages": "",
                "canonical": "User talk"
            },
            "4": {
                "id": 4,
                "case": "first-letter",
                "*": "Biblioteka Ossus",
                "canonical": "Project"
            },
            "5": {
                "id": 5,
                "case": "first-letter",
                "*": "Dyskusja Biblioteka Ossus",
                "subpages": "",
                "canonical": "Project talk"
            },
            "6": {
                "id": 6,
                "case": "first-letter",
                "*": "Plik",
                "canonical": "File"
            },
            "7": {
                "id": 7,
                "case": "first-letter",
                "*": "Dyskusja pliku",
                "subpages": "",
                "canonical": "File talk"
            },
            "8": {
                "id": 8,
                "case": "first-letter",
                "*": "MediaWiki",
                "canonical": "MediaWiki"
            },
            "9": {
                "id": 9,
                "case": "first-letter",
                "*": "Dyskusja MediaWiki",
                "subpages": "",
                "canonical": "MediaWiki talk"
            },
            "10": {
                "id": 10,
                "case": "first-letter",
                "*": "Szablon",
                "canonical": "Template"
            },
            "11": {
                "id": 11,
                "case": "first-letter",
                "*": "Dyskusja szablonu",
                "subpages": "",
                "canonical": "Template talk"
            },
            "12": {
                "id": 12,
                "case": "first-letter",
                "*": "Pomoc",
                "canonical": "Help"
            },
            "13": {
                "id": 13,
                "case": "first-letter",
                "*": "Dyskusja pomocy",
                "subpages": "",
                "canonical": "Help talk"
            },
            "14": {
                "id": 14,
                "case": "first-letter",
                "*": "Kategoria",
                "canonical": "Category"
            },
            "15": {
                "id": 15,
                "case": "first-letter",
                "*": "Dyskusja kategorii",
                "subpages": "",
                "canonical": "Category talk"
            },
            "104": {
                "id": 104,
                "case": "first-letter",
                "*": "S\u0142ownik Ossus",
                "subpages": "",
                "canonical": "S\u0142ownik Ossus"
            },
            "105": {
                "id": 105,
                "case": "first-letter",
                "*": "Dyskusja S\u0142ownika",
                "subpages": "",
                "canonical": "Dyskusja S\u0142ownika"
            },
            "106": {
                "id": 106,
                "case": "first-letter",
                "*": "Cytaty",
                "subpages": "",
                "canonical": "Cytaty"
            },
            "107": {
                "id": 107,
                "case": "first-letter",
                "*": "Dyskusja Cytat\u00f3w",
                "subpages": "",
                "canonical": "Dyskusja Cytat\u00f3w"
            },
            "110": {
                "id": 110,
                "case": "first-letter",
                "*": "Forum",
                "subpages": "",
                "canonical": "Forum"
            },
            "111": {
                "id": 111,
                "case": "first-letter",
                "*": "Forum talk",
                "canonical": "Forum talk"
            },
            "112": {
                "id": 112,
                "case": "first-letter",
                "*": "Portal",
                "subpages": "",
                "canonical": "Portal"
            },
            "113": {
                "id": 113,
                "case": "first-letter",
                "*": "Dyskusja Portalu",
                "subpages": "",
                "canonical": "Dyskusja Portalu"
            }
        }
    }
}