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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 worksheet(self, title):
 """Returns a worksheet with specified `title`. :param title: A title of a worksheet. If there're multiple worksheets with the same title, first one will be returned. :type title: int :returns: an instance of :class:`gsperad.models.Worksheet`. Example. Getting worksheet named 'Annual bonuses' """

        sheet_data = self.fetch_sheet_metadata()
        try:
            item = finditem(
                lambda x: x['properties']['title'] == title,
                sheet_data['sheets']
            )
            return Worksheet(self, item['properties'])
        except (StopIteration, KeyError):
            raise WorksheetNotFound(title)