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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 prior_const(C, alpha=0.001):
 """Constant prior of strength alpha. Prior is defined via b_ij=alpha for all i,j Parameters C : (M, M) ndarray or scipy.sparse matrix Count matrix alpha : float (optional) Value of prior counts Returns ------- B : (M, M) ndarray Prior count matrix """

    B = alpha * np.ones(C.shape)
    return B