blastn wright input whene is from makeblastdb

tools/blastn/blastn.rule.snakefile

@@ -8,9 +8,10 @@ def <step_name>__db():
         db_path = os.path.dirname(files[0])
     # if from makeblastdb step
     else:
-        db_name = os.path.basename(os.path.splitext(input.<step_name>__makeblastdb[0])[0])
-        db_path = os.path.dirname(input.<step_name>__makeblastdb[0])
-    
+        file = <step_name>__blastn_inputs()["blastdb"][0]
+        db_name = os.path.splitext(os.path.basename(file))[0]
+        db_path = os.path.dirname(file)
+        
     return { "db_name": db_name, "db_path": db_path }
 
 rule <step_name>__blastn: