fix round

Author: wtysos11

timediff.py

@@ -7,7 +7,7 @@
 
 import pyspark
 from pyspark.sql import SparkSession
-from pyspark.sql.functions import col
+from pyspark.sql.functions import col, round
 from pyspark.sql.functions import to_timestamp, current_timestamp
 from pyspark.sql.types import StructType, StructField, StringType, IntegerType, LongType