Spark supports Key-Value pairs RDD in Python trough a list of tuple.
A count of an RDD with tuple will return the number of tuples. A tuple can be seen as a row.
Spark RDD - (Creation|Construction|Initialization)
rdd = sc.parallelize([(1, 2), (3, 4)])
RDD: [(1, 2), (3, 4)]
Some Key-Value Transformations