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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 data_size(self, live_data=None):
 """Uses `nodetool info` to get the size of a node's data in KB."""

        if live_data is not None:
            warnings.warn("The 'live_data' keyword argument is deprecated.",
                          DeprecationWarning)
        output = self.nodetool('info')[0]
        return _get_load_from_info_output(output)