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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, items=None):
 """Return a new NGram object with the same settings, and referencing the same items. Copy is shallow in that each item is not recursively copied. Optionally specify alternate items to populate the copy. ['eggs', 'spam'] ['eggs', 'ham', 'spam'] ['bar', 'foo'] """

        return NGram(items if items is not None else self,
                     self.threshold, self.warp, self._key,
                     self.N, self._pad_len, self._pad_char)