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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 unpack_log_data(self, log_data, timestamp):
 """Unpack received logging data so it represent real values according to the configuration in the entry"""

        ret_data = {}
        data_index = 0
        for var in self.variables:
            size = LogTocElement.get_size_from_id(var.fetch_as)
            name = var.name
            unpackstring = LogTocElement.get_unpack_string_from_id(
                var.fetch_as)
            value = struct.unpack(
                unpackstring, log_data[data_index:data_index + size])[0]
            data_index += size
            ret_data[name] = value
        self.data_received_cb.call(timestamp, ret_data, self)