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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 copy(self):
 """ Return a copy of the dictionary. This is a middle-deep copy; the copy is independent of the original in all attributes that have mutable types except for: * The values in the dictionary Note that the Python functions :func:`py:copy.copy` and :func:`py:copy.deepcopy` can be used to create completely shallow or completely deep copies of objects of this class. """

        result = NocaseDict()
        result._data = self._data.copy()  # pylint: disable=protected-access
        return result