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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 ebr_data_transfer(token, dstore):
 """ Display the data transferred in an event based risk calculation """

    attrs = dstore['losses_by_event'].attrs
    sent = humansize(attrs['sent'])
    received = humansize(attrs['tot_received'])
    return 'Event Based Risk: sent %s, received %s' % (sent, received)