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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 inter_spin_hamiltonian(self, u_int, J_coup):
 """Calculates the interaction Hamiltonian. The Hund coupling is a fraction of the coulom interaction"""

        J_coup *= u_int
        h_int  = (u_int - 2*J_coup)/2.*self.oper['sumSz2']
        h_int += J_coup*self.oper['sumSz-sp2']
        h_int -= J_coup/2.*self.oper['sumSz-or2']
        h_int -= J_coup*self.oper['Sfliphop']

        return h_int