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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 _ParseMRUListExValue(self, registry_key):
 """Parses the MRUListEx value in a given Registry key. Args: registry_key (dfwinreg.WinRegistryKey):
 Windows Registry key that contains the MRUListEx value. Returns: mrulistex_entries: MRUListEx entries or None if not available. """

    mrulistex_value = registry_key.GetValueByName('MRUListEx')

    # The key exists but does not contain a value named "MRUList".
    if not mrulistex_value:
      return None

    mrulistex_entries_map = self._GetDataTypeMap('mrulistex_entries')

    context = dtfabric_data_maps.DataTypeMapContext(values={
        'data_size': len(mrulistex_value.data)})

    return self._ReadStructureFromByteStream(
        mrulistex_value.data, 0, mrulistex_entries_map, context=context)