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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 Open(self, filename):
 """Opens the database reader object. Args: filename (str):
 filename of the database. Returns: bool: True if successful. Raises: RuntimeError: if the version or string format of the database is not supported. """

    if not super(WinevtResourcesSqlite3DatabaseReader, self).Open(filename):
      return False

    version = self.GetMetadataAttribute('version')
    if not version or version != '20150315':
      raise RuntimeError('Unsupported version: {0:s}'.format(version))

    string_format = self.GetMetadataAttribute('string_format')
    if not string_format:
      string_format = 'wrc'

    if string_format not in ('pep3101', 'wrc'):
      raise RuntimeError('Unsupported string format: {0:s}'.format(
          string_format))

    self._string_format = string_format
    return True