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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 set_energy(self, spins, target_energy):
 """Set the energy of Theta with spins fixed to target_energy. Args: spins (dict):
 Spin values for a subset of the variables in Theta. target_energy (float):
 The desired energy for Theta with spins fixed. Notes: Add equality constraint to assertions. """

        spin_energy = self.energy(spins)
        self.assertions.add(Equals(spin_energy, limitReal(target_energy)))