Here is a trick though. You can map the Ctrl+Z keys.
This can be achieved by editing the .vimrc
file. Add the following lines in the '.vimrc` file.
nnoremap <c-z> :u<CR> " Avoid using this**
inoremap <c-z> <c-o>:u<CR>
This may not the a preferred way, but can be used.
** Ctrl+Z is used in Linux to suspend the ongoing program/process.