Base timestamp on mtime from tree

src/hostinfo/nettools.py

 import datetime
+import os
+import sys
 import hostinfo.util as util
 # File syntax is according to nettools manual:
 # IP-adress;hostnamn;kommasepareradeMAC-adresser;DHCP-grupp;LucatID;kommentar
@@ -31,12 +33,14 @@ def generate_row(ip,
                 % (ip, hostname, maclist, dhcp_group, owner, comment))
     return template
 
-def generate_row_tup(host):
+def generate_row_tup(tree, host):
     h = list(host)
     # Ensure proper length of tuple to unpack
     h = h + [""]*(6 - len(h))
     ip, hostname, maclist, dhcp_group, owner, _ = h
-    comment = datetime.datetime.now().isoformat(timespec='seconds')
+    mtime = datetime.datetime.fromtimestamp(int(max(tree._mtime,
+                                                    os.stat(sys.argv[0]).st_mtime)))
+    comment = "Batch generated: " + mtime.isoformat(timespec='seconds')
     return generate_row(ip, hostname, maclist, dhcp_group, owner, comment)
 
 def filter_nets(tree, options, ip):
@@ -92,6 +96,6 @@ def generate(tree, options):
 
     output = []
     for h in hosts:
-        output.append(generate_row_tup(h))
+        output.append(generate_row_tup(tree, h))
     return '\n'.join(output)