So you can't directly call your script with an argument the way you described above, but you can get pretty close with a simple wrapper script.
Here is something you could get started with:
from subprocess import call
results_file = sys.argv # file with search results
for row in csv.DictReader(openany(results_file)):
# Build a command line to call based on fields from splunk output
my_command = [ "myscript", row["host"], ]
This script will execute myscript <HOST> for every result returned by your search.