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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_common_cores(resources):
 """Retrieve the most common configured number of cores in the input file. """

    all_cores = []
    for vs in resources.values():
        cores = vs.get("cores")
        if cores:
            all_cores.append(int(vs["cores"]))
    return collections.Counter(all_cores).most_common(1)[0][0]