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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 _fully_random_weights(n_features, lam_scale, prng):
 """Generate a symmetric random matrix with zeros along the diagonal."""

    weights = np.zeros((n_features, n_features))
    n_off_diag = int((n_features ** 2 - n_features) / 2)
    weights[np.triu_indices(n_features, k=1)] = 0.1 * lam_scale * prng.randn(
        n_off_diag
    ) + (0.25 * lam_scale)
    weights[weights < 0] = 0
    weights = weights + weights.T
    return weights