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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 setdbo(self, bond1, bond2, dboval):
 """Set the double bond orientation for bond1 and bond2 based on this bond"""

        # this bond must be a double bond
        if self.bondtype != 2:
            raise FrownsError("To set double bond order, center bond must be double!")
        assert dboval in [DX_CHI_CIS, DX_CHI_TRANS, DX_CHI_NO_DBO], "bad dboval value"
        
        self.dbo.append(bond1, bond2, dboval)