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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 get_config_var_data(self, index, offset):
 """Get a chunk of data for a config variable."""


        if index == 0 or index > len(self.config_database.entries):
            return [Error.INVALID_ARRAY_KEY, b'']

        entry = self.config_database.entries[index - 1]
        if not entry.valid:
            return [ConfigDatabaseError.OBSOLETE_ENTRY, b'']

        if offset >= len(entry.data):
            return [Error.INVALID_ARRAY_KEY, b'']

        data_chunk = entry.data[offset:offset + 16]
        return [Error.NO_ERROR, data_chunk]