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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 find(self, title):
 """Fetch and return the first spreadsheet with the given title. Args: title(str):
 title/name of the spreadsheet to return Returns: SpreadSheet: new SpreadSheet instance Raises: KeyError: if no spreadsheet with the given ``title`` is found """

        files = backend.iterfiles(self._drive, name=title)
        try:
            return next(self[id] for id, _ in files)
        except StopIteration:
            raise KeyError(title)