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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 format_and_annualise(self, raw_cov_array):
 """ Helper method which annualises the output of shrinkage calculations, and formats the result into a dataframe :param raw_cov_array: raw covariance matrix of daily returns :type raw_cov_array: np.ndarray :return: annualised covariance matrix :rtype: pd.DataFrame """

        assets = self.X.columns
        return (
            pd.DataFrame(raw_cov_array, index=assets, columns=assets) * self.frequency
        )