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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 subdict(super_dict, keys):
 """ Returns a subset of the super_dict with the specified keys. """

    sub_dict = {}
    valid_keys = super_dict.keys()
    for key in keys:
        if key in valid_keys:
            sub_dict[key] = super_dict[key]

    return sub_dict