docstr: Randomly convert RGB image(s) to Grayscale w/ some probability,
  NOTE: Always retains the 3 channels if image is grayscaled
  
  p : a float
      probability that image will be grayscaled
code: def __init__(self, p=0.5):
      """
      Randomly convert RGB image(s) to Grayscale w/ some probability,
      NOTE: Always retains the 3 channels if image is grayscaled
  
      p : a float
          probability that image will be grayscaled
      """
      self.p = p
  
imports: import random
  import torch
  from torchvision.transforms.functional import to_tensor
  import numpy
  from ..utils import th_random_choice
label_desc: Use image node_id 1 to create a new RandomGrayscale object  with example: obj = RandomGrayscale(p)