code: def hash_file(path, block_size=65536):
      """Returns SHA256 checksum of a file
  
      Args:
          path (string): Absolute file path of file to hash
  
          block_size (int, optional): Number of bytes to read per block
      """
      sha256 = hashlib.sha256()
      with open(path, "rb") as f:
          for block in iter(lambda: f.read(block_size), b""):
              sha256.update(block)
      return sha256.hexdigest()
  
imports: from __future__ import absolute_import, print_function, division, unicode_literals
  import imp
  import sys
  import os
  import hashlib
  import json
  import numpy
  from sqlalchemy import create_engine
  from sqlalchemy.orm import Session
  from six import exec_, iteritems
  from sklearn import datasets
  from sklearn import model_selection
  from xcessiv import app, exceptions
label_desc: Use image node_id 1 for calling a global function with example usage: hash_file(path, block_size) and returns: sha256