Open A Floating Window In Neovim With Lua

This is how I'm openeing floating windows in Neovim plugins. It returns the buffer number of the floating window and sets a keymap to close the window with ESC in normal mode.

local open_floating_window = function()
    local active_buffer = vim.api.nvim_get_current_buf()
    local opts = {
        style="minimal", 
        relative='editor',
        border='single'
    }
    opts.width = vim.api.nvim_win_get_width(0) - 18
    opts.height = vim.api.nvim_win_get_height(0) - 12
    opts.col = (vim.api.nvim_win_get_width(0) / 2) - (opts.width / 2)
    opts.row = (vim.api.nvim_win_get_height(0) / 2) - (opts.height / 2)
    floating_buffer = vim.api.nvim_create_buf(false, true)
    floating_window = vim.api.nvim_open_win(floating_buffer, true, opts)
    vim.keymap.set("n", "<ESC>", function()
        vim.api.nvim_win_close(floating_window, true)
        end, 
        { buffer = floating_buffer }
    )
    return floating_window
end

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