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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 GetValues(self):
 """Retrieves all values within the key. Returns: generator[WinRegistryValue]: Windows Registry value generator. """

    if not self._registry_key and self._registry:
      self._GetKeyFromRegistry()

    if self._registry_key:
      return self._registry_key.GetValues()

    return iter([])