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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 _check_completeness_table(completeness, catalogue):
 """ Generates the completeness table according to different instances """

    if isinstance(completeness, np.ndarray) and np.shape(completeness)[1] == 2:
        return completeness
    elif isinstance(completeness, float):
        return np.array([[float(np.min(catalogue.data['year'])),
                          completeness]])
    elif completeness is None:
        return np.array([[float(np.min(catalogue.data['year'])),
                          np.min(catalogue.data['magnitude'])]])
    else:
        raise ValueError('Completeness representation not recognised')