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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 _nominal_kernel(x, y, out):
 """Number of features that match exactly"""

    for i in range(x.shape[0]):
        for j in range(y.shape[0]):
            out[i, j] += (x[i, :] == y[j, :]).sum()

    return out