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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_norms_of_rows(data_frame, method):
 """ return a column vector containing the norm of each row """

    if method == 'vector':
        norm_vector = np.linalg.norm(data_frame.values, axis=1)
    elif method == 'last':
        norm_vector = data_frame.iloc[:, -1].values
    elif method == 'mean':
        norm_vector = np.mean(data_frame.values, axis=1)
    elif method == 'first':
        norm_vector = data_frame.iloc[:, 0].values
    else:
        raise ValueError("no normalization method '{0}'".format(method))
    return norm_vector