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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 pca_to_mapping(pca,**extra_props):
 """ A helper to return a mapping of a PCA result set suitable for reconstructing a planar error surface in other software packages kwargs: method (defaults to sampling axes) """

    from .axes import sampling_axes
    method = extra_props.pop('method',sampling_axes)
    return dict(
        axes=pca.axes.tolist(),
        covariance=method(pca).tolist(),
        **extra_props)