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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 delta_hv(scatterer):
 """ Delta_hv for the current setup. Args: scatterer: a Scatterer instance. Returns: Delta_hv [rad]. """

    Z = scatterer.get_Z()
    return np.arctan2(Z[2,3] - Z[3,2], -Z[2,2] - Z[3,3])