>>> df = spark.createDataFrame([(1, "A", [1,2,3]), (2, "B", [3,5])],["col1", "col2", "col3"])
>>> from pyspark.sql.functions import explode
>>> df.withColumn("col3", explode(df.col3)).show()
+----+----+----+
|col1|col2|col3|
+----+----+----+
|   1|   A|   1|
|   1|   A|   2|
|   1|   A|   3|
|   2|   B|   3|
|   2|   B|   5|
+----+----+----+