code: def range(self, start, end=None, step=1, numSlices=None):
          
          if end is None:
              end = start
              start = 0
  
          return self.parallelize(xrange(start, end, step), numSlices)
docs: Create a new RDD of int containing elements from `start` to `end`
          (exclusive), increased by `step` every element. Can be called the same
          way as python's built-in range() function. If called with a single argument,
          the argument is interpreted as `end`, and `start` is set to 0.
  
          :param start: the start value
          :param end: the end value (exclusive)
          :param step: the incremental step (default: 1)
          :param numSlices: the number of partitions of the new RDD
          :return: An RDD of int
  
          >>> sc.range(5).collect()
          [0, 1, 2, 3, 4]
          >>> sc.range(2, 4).collect()
          [2, 3]
          >>> sc.range(1, 7, 2).collect()
          [1, 3, 5]