Can opener not necessary for metal cans. I’ve done this for years and even a toddler could do it.
Rub the top of the can where the lid is crimped on to the body of the can on cement sidewalk a few times until the top lip is worn down. You only have to grind through a thin piece of metal. Once you’re through, remove the lid and drink your cold chicken noodle soup. This method is shown on youtube. can get through a can faster than with the P-38.
It requires a sidewalk. We don’t have sidewalks on my street.