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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 spin_gen(particles, index, gauge=1):
 """Generates the generic spin operator in z basis for a system of N=particles and for the selected spin index name. where index=0..N-1 The gauge term sets the behavoir for a system away from half-filling"""

    mat = np.zeros((2**particles, 2**particles))

    flipper = 2**index
    for i in range(2**particles):
        ispin = btest(i, index)
        if ispin == 1:
            mat[i ^ flipper, i] = 1
        else:
            mat[i ^ flipper, i] = gauge
    return mat