code: def _GetFreeFlaskPort():
      """Get a free flask port."""
      # We will prefer to use 5000. If not, we will then pick a random port.
      sock = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
      result = sock.connect_ex(("127.0.0.1", 5000))
      if result == 0:
          return 5000
      else:
          s = socket.socket()
          s.bind(("", 0))
          port = s.getsockname()[1]
          s.close()
          # Race condition: between the interval we close the socket and actually
          # start a mint process, another process might have occupied the port. We
          # don't do much here as this is mostly for convenience in research
          # rather than 24x7 service.
          return port
  
imports: import collections
  import contextlib
  from google.protobuf.message import Message
  from multiprocessing import Process
  import os
  from collections import defaultdict
  import logging
  import numpy
  from past.builtins import basestring
  import shutil
  import socket
  import tempfile
  from caffe2.proto import caffe2_pb2
  from caffe2.python import scope, utils
  from caffe2.python.lazy import TriggerLazyImport
  import caffe2.python._import_c_extension
label_desc: Use image node_id 2 for calling a global function with example usage: _GetFreeFlaskPort() and returns: int, port