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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_convergence(newX, oldX, e_rel):
 """Check that the algorithm converges using Langville 2014 criteria Uses the check from Langville 2014, Section 5, to check if the NMF algorithm has converged. """

    # Calculate the norm for columns and rows, which can be used for debugging
    # Otherwise skip, since it takes extra processing time
    new_old = newX*oldX
    old2 = oldX**2
    norms = [np.sum(new_old), np.sum(old2)]
    convergent = norms[0] >= (1-e_rel**2)*norms[1]
    return convergent, norms