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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 unpickle_args(items):
    '''Takes a dict and unpickles values whose keys are found in
    '_pickled' key.

    >>> unpickle_args({'_pickled': ['foo']. 'foo': ['I3%0A.']})
    {'foo': 3}
    '''
    # Technically there can be more than one _pickled value. At this point
    # we'll just use the first one
    pickled= items.pop('_pickled', None)
    if pickled is None:
        return items

    pickled_keys = pickled[0].split(',')
    ret = {}
    for key, vals in items.items():
        if key in pickled_keys:
            ret[key] = [pickle.loads(val) for val in vals]
        else:
            ret[key] = vals
    return ret