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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 _ParseFValue(self, registry_key):
 """Parses an F value. Args: registry_key (dfwinreg.WinRegistryKey):
 Windows Registry key. Returns: f_value: F value stored in the Windows Registry key. Raises: ParseError: if the Windows Registry key does not contain an F value or F value cannot be parsed. """

    registry_value = registry_key.GetValueByName('F')
    if not registry_value:
      raise errors.ParseError(
          'missing value: "F" in Windows Registry key: {0:s}.'.format(
              registry_key.name))

    f_value_map = self._GetDataTypeMap('f_value')

    try:
      return self._ReadStructureFromByteStream(
          registry_value.data, 0, f_value_map)
    except (ValueError, errors.ParseError) as exception:
      raise errors.ParseError(exception)