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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def ExtractEvents(self, parser_mediator, registry_key, **kwargs):
 """Extracts events from a Terminal Server Client Windows Registry key. Args: parser_mediator (ParserMediator):
 mediates interactions between parsers and other components, such as storage and dfvfs. registry_key (dfwinreg.WinRegistryKey):
 Windows Registry key. """

    mru_values_dict = {}
    for subkey in registry_key.GetSubkeys():
      username_value = subkey.GetValueByName('UsernameHint')

      if (username_value and username_value.data and
          username_value.DataIsString()):
        username = username_value.GetDataAsObject()
      else:
        username = 'N/A'

      mru_values_dict[subkey.name] = username

      event_data = windows_events.WindowsRegistryEventData()
      event_data.key_path = subkey.path
      event_data.offset = subkey.offset
      event_data.regvalue = {'Username hint': username}
      event_data.source_append = self._SOURCE_APPEND

      event = time_events.DateTimeValuesEvent(
          subkey.last_written_time, definitions.TIME_DESCRIPTION_WRITTEN)
      parser_mediator.ProduceEventWithEventData(event, event_data)

    event_data = windows_events.WindowsRegistryEventData()
    event_data.key_path = registry_key.path
    event_data.offset = registry_key.offset
    event_data.regvalue = mru_values_dict
    event_data.source_append = self._SOURCE_APPEND

    event = time_events.DateTimeValuesEvent(
        registry_key.last_written_time, definitions.TIME_DESCRIPTION_WRITTEN)
    parser_mediator.ProduceEventWithEventData(event, event_data)