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function string.split(s, pattern, maxsplit)

    if type(s) ~= "string" or type(pattern) ~= "string" or type(maxsplit) ~= "string" then

        return nil

    end

    if pattern == nil then

        pattern = " "

    end

    if maxsplit == nil then

        maxsplit = -1

    end

    if string.find(s, pattern) == nil then

        return {s}

    end

    local strings = {}
    local index = 1
    local last_index = 1

    while true do

        index = string.find(s, pattern, index)

        if index == nil or #strings == maxsplit then

            table.insert(strings, string.sub(s, last_index))

            return strings

        end

        table.insert(strings, string.sub(s, last_index, index - 1))
        index = index + #pattern
        last_index = index

    end

end