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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 _sort_io_counters(process, sortedby='io_counters', sortedby_secondary='memory_percent'):
 """Specific case for io_counters Sum of io_r + io_w"""

    return process[sortedby][0] - process[sortedby][2] + process[sortedby][1] - process[sortedby][3]