class_docstr: MIME-types datastore.
  
  This datastore can handle information from mime.types-style files
  and supports basic determination of MIME type from a filename or
  URL, and can guess a reasonable extension given a MIME type.
code: def _read_windows_registry(cls, add_type):
      def enum_types(mimedb):
          i = 0
          while True:
              try:
                  ctype = _winreg.EnumKey(mimedb, i)
              except OSError:
                  break
              else:
                  if "\0" not in ctype:
                      yield ctype
              i += 1
  
      with _winreg.OpenKey(_winreg.HKEY_CLASSES_ROOT, "") as hkcr:
          for subkeyname in enum_types(hkcr):
              try:
                  with _winreg.OpenKey(hkcr, subkeyname) as subkey:
                      # Only check file extensions
                      if not subkeyname.startswith("."):
                          continue
                      # raises OSError if no 'Content Type' value
                      mimetype, datatype = _winreg.QueryValueEx(
                          subkey, "Content Type"
                      )
                      if datatype != _winreg.REG_SZ:
                          continue
                      add_type(mimetype, subkeyname)
              except OSError:
                  continue
  
imports: import os
  import sys
  import posixpath
  import urllib.parse
label_desc: Use image node_id 9 for calling the MimeTypes obj's underlying member method code with example usage: obj._read_windows_registry(cls, add_type) without return types