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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_lambda(sortedby='cpu_percent', sortedby_secondary='memory_percent'):
 """Return a sort lambda function for the sortedbykey"""

    ret = None
    if sortedby == 'io_counters':
        ret = _sort_io_counters
    elif sortedby == 'cpu_times':
        ret = _sort_cpu_times
    return ret