toggle neovim terminal window

init.vim

let s:term_window = -1
let s:term_buffer = -1
let s:term_job_id = -1

function! TerminalOpen()
    " Check if buffer exists, if not create a window and a buffer
    if !bufexists(s:term_buffer)
    " Creates a window call monkey_terminal
    new local_terminal

	" disable line numbers
	setlocal nonumber norelativenumber
    " Moves to the window the right the current one
    " wincmd L
    let s:term_job_id = termopen($SHELL, { 'detach': 1 })

     " Change the name of the buffer to "Terminal 1"
     silent file Terminal\ 1
     " Gets the id of the terminal window
     let s:term_window = win_getid()
     let s:term_buffer = bufnr('%')

    " The buffer of the terminal won't appear in the list of the buffers
    " when calling :buffers command
    set nobuflisted
  else
    if !win_gotoid(s:term_window)
    split
    " Moves to the window below the current one
    " wincmd L   
    buffer Terminal\ 1
     " Gets the id of the terminal window
     let s:term_window = win_getid()
    endif
  endif
  " be in insert mode immediately
  startinsert
endfunction

function! TerminalToggle()
  if win_gotoid(s:term_window)
	hide
  else
    call TerminalOpen()
  endif
endfunction

" toggle terminal window
nnoremap <silent> <C-z> :call TerminalToggle()<cr>
tnoremap <silent> <C-z> <C-\><C-n>:call TerminalToggle()<cr>