```python:/usr/local/sbin/writehostid
#!/usr/bin/env python3
from struct import pack
import argparse
import ipaddress
parser = argparse.ArgumentParser()
parser.add_argument('-f', '--file', type=str, required=False, help='Path to hostid file', default="/etc/hostid")
parser.add_argument("ipv4addr", help="IPv4 Address")
args = parser.parse_args()
hostid = pack("I",int(ipaddress.IPv4Address(args.ipv4addr)))
open(args.file,"wb").write(hostid)
```
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