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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 openall(self, title=None):
 """Opens all available spreadsheets. :param title: (optional) If specified can be used to filter spreadsheets by title. :type title: str :returns: a list of :class:`~gspread.models.Spreadsheet` instances. """

        spreadsheet_files = self.list_spreadsheet_files()

        return [
            Spreadsheet(self, dict(title=x['name'], **x))
            for x in spreadsheet_files
        ]