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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 get_worksheet(self, index):
 """Returns a worksheet with specified `index`. :param index: An index of a worksheet. Indexes start from zero. :type index: int :returns: an instance of :class:`gsperad.models.Worksheet` or `None` if the worksheet is not found. Example. To get first worksheet of a spreadsheet: """

        sheet_data = self.fetch_sheet_metadata()

        try:
            properties = sheet_data['sheets'][index]['properties']
            return Worksheet(self, properties)
        except (KeyError, IndexError):
            return None