Return an iterator over this instruction's operands.
        The iterator will yield a ValueRef for each operand.

def operands(self):
        """
        Return an iterator over this instruction's operands.
        The iterator will yield a ValueRef for each operand.
        """
        if not self.is_instruction:
            raise ValueError('expected instruction value, got %s'
                             % (self._kind,))
        it = ffi.lib.LLVMPY_InstructionOperandsIter(self)
        parents = self._parents.copy()
        parents.update(instruction=self)
        return _OperandsIterator(it, parents)