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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 append_row(self, values, value_input_option='RAW'):
 """Adds a row to the worksheet and populates it with values. Widens the worksheet if there are more values than columns. :param values: List of values for the new row. :param value_input_option: (optional) Determines how input data should be interpreted. See `ValueInputOption`_ in the Sheets API. :type value_input_option: str .. _ValueInputOption: https://developers.google.com/sheets/api/reference/rest/v4/ValueInputOption """

        params = {
            'valueInputOption': value_input_option
        }

        body = {
            'values': [values]
        }

        return self.spreadsheet.values_append(self.title, params, body)