<s>[INST] Please, write a python script to quickly synchronise a large list of files between S3 and local storage. [/INST] One option to synchronize a large list of files between S3 and local storage would be to use the aws cli. You can call the aws cli using ‘os.System’ in python. Here is an example: 
‘’’Python
import os

cmd = 'aws s3 sync s3://source-bucket/ my-dir'
os.system(cmd)
‘’’

Is there something else I can do for you?</s>\ <s>[INST] Please explain that to me line by line. [/INST] - load the Operating System model with `import os`
- `cmd = 'aws s3 sync s3://source-bucket/ my-dir'` stores the aws cli command in a variable
- `os.system(cmd)` execute the previous command</s>\ <s>[INST] What is the operating system model? [/INST] 