instruction: Create a Dockerfile for fundamentals
output: ```dockerfile
  From a terminal on your Docker host, run the following docker run commands.
  The strings at the end are the IDs of each container.
  
  $ docker run -dit --name my_container_1 acme/my-final-image:1.0 bash \
   && docker run -dit --name my_container_2 acme/my-final-image:1.0 bash \
   && docker run -dit --name my_container_3 acme/my-final-image:1.0 bash \
   && docker run -dit --name my_container_4 acme/my-final-image:1.0 bash \
   && docker run -dit --name my_container_5 acme/my-final-image:1.0 bash
  
  40ebdd7634162eb42bdb1ba76a395095527e9c0aa40348e6c325bd0aa289423c
  a5ff32e2b551168b9498870faf16c9cd0af820edf8a5c157f7b80da59d01a107
  3ed3c1a10430e09f253704116965b01ca920202d52f3bf381fbb833b8ae356bc
  939b3bf9e7ece24bcffec57d974c939da2bdcc6a5077b5459c897c1e2fa37a39
  cddae31c314fbab3f7eabeb9b26733838187abc9a2ed53f97bd5b04cd7984a5a
  Run the docker ps command with the --size option to verify the 5 containers
  are running, and to see each container's size.
  
  $ docker ps --size --format "table {{.ID}}\t{{.Image}}\t{{.Names}}\t{{.Size}}"
  
  CONTAINER ID IMAGE NAMES SIZE
  cddae31c314f acme/my-final-image:1.0 my_container_5 0B (virtual 7.75MB)
  939b3bf9e7ec acme/my-final-image:1.0 my_container_4 0B (virtual 7.75MB)
  3ed3c1a10430 acme/my-final-image:1.0 my_container_3 0B (virtual 7.75MB)
  a5ff32e2b551 acme/my-final-image:1.0 my_container_2 0B (virtual 7.75MB)
  40ebdd763416 acme/my-final-image:1.0 my_container_1 0B (virtual 7.75MB)
  The output above shows that all containers share the image's read-only layers
  (7.75MB), but no data was written to the container's filesystem, so no additional
  storage is used for the containers.Advanced: metadata and logs storage used for containers
  
  NoteThis step requires a Linux machine, and doesn't work on Docker Desktop, as
  it requires access to the Docker Daemon's file storage.While the output of docker ps provides you information about disk space
  consumed by a container's writable layer, it doesn't include information
  about metadata and log-files stored for each container.More details can be obtained by exploring the Docker Daemon's storage
  location (/var/lib/docker by default).
  
  $ sudo du -sh /var/lib/docker/containers/*
  
  36K /var/lib/docker/containers/3ed3c1a10430e09f253704116965b01ca920202d52f3bf381fbb833b8ae356bc
  36K /var/lib/docker/containers/40ebdd7634162eb42bdb1ba76a395095527e9c0aa40348e6c325bd0aa289423c
  36K /var/lib/docker/containers/939b3bf9e7ece24bcffec57d974c939da2bdcc6a5077b5459c897c1e2fa37a39
  36K /var/lib/docker/containers/a5ff32e2b551168b9498870faf16c9cd0af820edf8a5c157f7b80da59d01a107
  36K /var/lib/docker/containers/cddae31c314fbab3f7eabeb9b26733838187abc9a2ed53f97bd5b04cd7984a5a
  Each of these containers only takes up 36k of space on the filesystem.Per-container storageTo demonstrate this, run the following command to write the word 'hello' to
  a file on the container's writable layer in containers my_container_1,
  my_container_2, and my_container_3:
  
  $ for i in {1..3}; do docker exec my_container_$i sh -c 'printf hello > /out.txt'; done
  Running the docker ps command again afterward shows that those containers
  now consume 5 bytes each. This data is unique to each container, and not
  shared. The read-only layers of the containers aren't affected, and are still
  shared by all containers.
  
  $ docker ps --size --format "table {{.ID}}\t{{.Image}}\t{{.Names}}\t{{.Size}}"
  
  CONTAINER ID IMAGE NAMES SIZE
  cddae31c314f acme/my-final-image:1.0 my_container_5 0B (virtual 7.75MB)
  939b3bf9e7ec acme/my-final-image:1.0 my_container_4 0B (virtual 7.75MB)
  3ed3c1a10430 acme/my-final-image:1.0 my_container_3 5B (virtual 7.75MB)
  a5ff32e2b551 acme/my-final-image:1.0 my_container_2 5B (virtual 7.75MB)
  40ebdd763416 acme/my-final-image:1.0 my_container_1 5B (virtual 7.75MB)
  The previous examples illustrate how copy-on-write filesystems help make
  containers efficient. Not only does copy-on-write save space, but it also
  reduces container start-up time. When you create a container (or multiple
  containers
  ```