Change to distutils, because packaging module isn't always installed

dnscan.py

@@ -4,7 +4,7 @@
 # Licensed under GPLv3, see LICENSE for details
 #
 from __future__ import print_function
-from packaging import version
+from distutils.version import LooseVersion
 
 import os
 import platform
@@ -44,7 +44,7 @@
     print("FATAL: Module dnspython missing (python-dnspython)")
     sys.exit(1)
 
-if (version.parse(dns.__version__) < version.parse("2.0.0")):
+if (LooseVersion(dns.__version__) < LooseVersion("2.0.0")):
     print("dnscan requires dnspython 2.0.0 or greater.\nYou can install it with `pip install -r requirements.txt`")
     sys.exit(1)