diff --git a/snekmer/rules/model.smk b/snekmer/rules/model.smk
index 3edbf40..1a239e7 100644
--- a/snekmer/rules/model.smk
+++ b/snekmer/rules/model.smk
@@ -89,12 +89,15 @@ out_dir = skm.io.define_output_dir(
     config["alphabet"], config["k"], nested=config["nested_output"]
 )
 
+
 # show warnings if files excluded
 onstart:
     [
-        skm.utils.check_n_seqs(fa, config["model"]["cv"], show_warning=True) for fa in input_files
+        skm.utils.check_n_seqs(fa, config["model"]["cv"], show_warning=True)
+        for fa in input_files
     ]
 
+
 # define output files to be created by snekmer
 rule all:
     input: