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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 _make_minimal(dictionary):
 """ This function removes all the keys whose value is either None or an empty dictionary. """

    new_dict = {}
    for key, value in dictionary.items():
        if value is not None:
            if isinstance(value, dict):
                new_value = _make_minimal(value)
                if new_value:
                    new_dict[key] = new_value
            else:
                new_dict[key] = value
    return new_dict