class_docstr: Draw activations of a specific layer for a given input
code: def __init__(self, batch_size=None):
      self.batch_size = batch_size
  
file_path: tf-explain/tf_explain/core/activations.py
imports: import numpy
  import tensorflow
  from tf_explain.utils.display import filter_display
  from tf_explain.utils.saver import save_grayscale
label_desc: Use image node_id 1 to create a new ExtractActivations object  with example: obj = ExtractActivations(batch_size)