diff --git a/covid_analysis/transforms.py b/covid_analysis/transforms.py
index 21f4b89..e8a36d1 100644
--- a/covid_analysis/transforms.py
+++ b/covid_analysis/transforms.py
@@ -21,4 +21,4 @@ def clean_spark_cols(pdf):
 # Convert index to column (works with pandas API on Spark, too).
 def index_to_col(df, colname):
     df[colname] = df.index
-    return df
\ No newline at end of file
+    return df