class_docstr: Partition generator using the Chinese Restaurant Process (CRP).
  
  The first element creates the first partition. The n-th element chooses to
  either create a new partition with probability `alpha / (n - 1 + alpha)`, or
  join an existing partition `B_k` with probabiliy `|B_k|/(n - 1 + alpha)` where
  `|B_k|` is the size of `B_k`.
  
  Attributes:
    alpha: A positive float representing the discount parameter of CRP.
code: def __init__(self, alpha: float):
      if alpha <= 0:
          raise ValueError(
              f"alpha must be a positive value, not {alpha}."
          )
  
      self.alpha = alpha
  
imports: from typing import List
  import numpy
label_desc: Use image node_id 1 to create a new CRPGenerator object  with example: obj = CRPGenerator(alpha)