Hello Guys. How do i block malicious senders in office 365 security and compliance?

ankit shukla 

How can I use import-csv with get-blockedsenderaddress to see which users are blocked based on a list of email addresses?

Also, once the list is checked, can I add a block for those that may not have one on the lists

Finally i would like to use the same/modified list for remove-blocked sender address.

Thanks,
A