code: def compute_block_lower(index, shape):
      if len(index) != len(shape):
          raise Exception(
              "The fields `index` and `shape` must have the "
              "same length, but `index` is {} and `shape` is "
              "{}.".format(index, shape)
          )
      return [elem * BLOCK_SIZE for elem in index]
  
imports: import numpy
  import ray
  import ray.experimental.array.remote
label_desc: Use image node_id 2 for calling the DistArray obj's underlying member method code with example usage: obj.compute_block_lower(index, shape) and returns: unknown