gstlal_inspiral_create_dt_dphi_snr_ratio_pdfs_dag: fix typo

gstlal-inspiral/bin/gstlal_inspiral_create_dt_dphi_snr_ratio_pdfs_dag

@@ -16,6 +16,7 @@
 # with this program; if not, write to the Free Software Foundation, Inc.,
 # 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301, USA.
 
+import os
 from glue import pipeline
 from gstlal import inspiral_pipe
 from gstlal import dagparts as gstlaldagparts
@@ -31,7 +32,7 @@ margJob = inspiral_pipe.generic_job("gstlal_inspiral_create_dt_dphi_snr_ratio_pd
 
 for start in range(0,3345408,10000):
 	stop = start + 10000
-	inspiral_pipe.generic_node(margJob, dag, parent_nodes = [], opts = {"" : [start, stop]})
+	inspiral_pipe.generic_node(margJob, dag, parent_nodes = [], opts = {"" : [str(start), str(stop)]})
 dag.write_sub_files()
 dag.write_dag()
 dag.write_script()