code: def get_home_dir(require_writable=False):
      """Return the 'home' directory, as a unicode string.
  
      Uses os.path.expanduser('~'), and checks for writability.
  
      See stdlib docs for how this is determined.
      $HOME is first priority on *ALL* platforms.
  
      Parameters
      ----------
  
      require_writable : bool [default: False]
          if True:
              guarantees the return value is a writable directory, otherwise
              raises HomeDirError
          if False:
              The path is resolved, but it is not guaranteed to exist or be writable.
      """
  
      homedir = os.path.expanduser("~")
      # Next line will make things work even when /home/ is a symlink to
      # /usr/home as it is on FreeBSD, for example
      homedir = os.path.realpath(homedir)
  
      if not _writable_dir(homedir) and os.name == "nt":
          # expanduser failed, use the registry to get the 'My Documents' folder.
          try:
              try:
                  import winreg as wreg  # Py 3
              except ImportError:
                  import _winreg as wreg  # Py 2
              key = wreg.OpenKey(
                  wreg.HKEY_CURRENT_USER,
                  "Software\Microsoft\Windows\CurrentVersion\Explorer\Shell Folders",
              )
              homedir = wreg.QueryValueEx(key, "Personal")[0]
              key.Close()
          except:
              pass
  
      if (not require_writable) or _writable_dir(homedir):
          return py3compat.cast_unicode(homedir, fs_encoding)
      else:
          raise HomeDirError(
              "%s is not a writable dir, "
              "set $HOME environment variable to override" % homedir
          )
  
imports: import os
  import sys
  import errno
  import shutil
  import random
  import glob
  from warnings import warn
  from hashlib import md5
  from IPython.utils.process import system
  from IPython.utils import py3compat
  from IPython.utils.decorators import undoc
label_desc: Use image node_id 7 for calling a global function with example usage: get_home_dir(require_writable) and returns: py3compat