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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 _recursive_getitem(d, key):
 """ Descend into a dict of dicts to return the one that contains a given key. Every value in the dict must be another dict. """

    if key in d:
        return d
    else:
        for v in d.values():
            return _recursive_getitem(v, key)
        else:
            raise KeyError('Key not found: {}'.format(key))