code: def well_metadata_tokens(tokens):
      """Return the well row and well column tokens out of a set of metadata tokens"""
  
      well_row_token = None
      well_column_token = None
      for token in tokens:
          if is_well_row_token(token):
              well_row_token = token
          if is_well_column_token(token):
              well_column_token = token
      return well_row_token, well_column_token
  
imports: import logging
  import os
  import re
  import shutil
  import sys
  import tempfile
  import urllib.request
  from urllib.parse import parse_qs, unquote, urlparse
  from urllib.request import urlopen
  import boto3
  import numpy
  import pkg_resources
  import scipy.io
  from google.cloud import storage
  from google.cloud.exceptions import NotFound
  from google.auth.exceptions import DefaultCredentialsError
  from ..constants.image import ALL_IMAGE_EXTENSIONS, FILE_SCHEME, PASSTHROUGH_SCHEMES, SUPPORTED_MOVIE_EXTENSIONS
  from ..constants.measurement import FTR_WELL
  from .measurement import is_well_column_token, is_well_row_token
label_desc: Use image node_id 3 for calling a global function with example usage: well_metadata_tokens(tokens) and returns: well_row_token,  well_column_token