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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_total_size_trans(self, entries):
 """ Returns the total size of a collection of entries - transferred. NOTE: use with har file generated with chrome-har-capturer :param entries: ``list`` of entries to calculate the total size of. """

        size = 0
        for entry in entries:
            if entry['response']['_transferSize'] > 0:
                size += entry['response']['_transferSize']
        return size