This is what TAC sent me couple of years back and honestly, I find best method, or you could se script via api command line from dashboard to place multiple entries.
--->To add address-range via API:
mgmt_cli add address-range --batch address-ranges_full.csv
#cat address-ranges_full.csv
name,ip-address-first,ip-address-last
range1,10.0.0.0,10.0.0.100
---> To add a network via API:
mgmt_cli add network --batch networks.csv
#cat networks.csv
name,subnet,subnet-mask
network1,10.10.10.0,255.255.255.0
network2,20.20.20.0,255.255.255.0
network3,30.30.30.0,255.255.255.0
---> To add a host
mgmt_cli add host --batch test.csv
#cat test.csv
name,ip-address
obj1,192.168.1.1
If you do it via dashboard api cli, you would do something like this (can acomodate multiple entries)
add host name "BAD_185.206.24.70" ip-address "185.206.24.70"