The support of all the operators in the PauliSum object.

        :returns: A list of all the qubits in the sum of terms.
        :rtype: list

def get_qubits(self):
        """
        The support of all the operators in the PauliSum object.

        :returns: A list of all the qubits in the sum of terms.
        :rtype: list
        """
        return list(set().union(*[term.get_qubits() for term in self.terms]))