Gettinng back cells after being deleted in Colab

I often delete code in Colab, by accident, and for some reason when I try to do undo code deletion it does not work. So basically when I do this I want to get my cells back somehow. Is there any way to do this, like take a look at the code that Colab is running, because my cells are probably still there. Another option would be to somehow see cells that have been previously deleted. Please help me. Any other solutions would be nice.