code: def Bias(alpha, X, y, kernel=dot):
      """Compute classification bias."""
      sv1, sv2 = SupportVectors(alpha, y, epsilon=1e-6)
      pt1, pt2 = X[sv1[0], :], X[sv2[0], :]
      k1, k2 = kernel(X, pt1), kernel(X, pt2)
      return -0.5 * (sum(alpha * y * k1) + sum(alpha * y * k2))
  
imports: from numpy import multiply, asarray, dot, transpose, sum
label_desc: Use image node_id 4 for calling a global function with example usage: Bias(alpha, X, y, kernel) and returns: unknown