Update Snakefile

Snakefile

@@ -1,6 +1,6 @@
-import os
 import glob
 import multiprocessing
+import os
 from python import down_ascn 
 from python import fasta_cleaner
 from python import concatenate_fastas
@@ -143,4 +143,4 @@ rule build_tree:
     output:
         img="Tree.svg"
     run:
-        newick_tree_visualizer.tree_generator(input.tree, output.img)        
+        newick_tree_visualizer.tree_generator(input.tree, output.img)