def dagNodeVariablesUsed(self, dagNode):
        singleDollarList = list()
        doubleDollarList = list()
        for input in dagNode.inputs():
            vps = depends_variables.present(dagNode.inputValue(input.name, variableSubstitution=False))
            vss = (list(), list())
            vss2 = (list(), list())
            if dagNode.inputRange(input.name, variableSubstitution=False):
                vss = depends_variables.present(dagNode.inputRange(input.name, variableSubstitution=False)[0])
                vss2 = depends_variables.present(dagNode.inputRange(input.name, variableSubstitution=False)[1])
            singleDollarList += vps[0] + vss[0] + vss2[0]
            doubleDollarList += vps[1] + vss[1] + vss2[1]
        for attribute in dagNode.attributes():
            vps = depends_variables.present(dagNode.attributeValue(attribute.name, variableSubstitution=False))
            vss = (list(), list())
            vss2 = (list(), list())
            if dagNode.attributeRange(attribute.name, variableSubstitution=False):
                vss = depends_variables.present(dagNode.attributeRange(attribute.name, variableSubstitution=False)[0])
                vss2 = depends_variables.present(dagNode.attributeRange(attribute.name, variableSubstitution=False)[1])
            singleDollarList += vps[0] + vss[0] + vss2[0]
            doubleDollarList += vps[1] + vss[1] + vss2[1]
        for output in dagNode.outputs():
            for subName in output.subOutputNames():
                vps = depends_variables.present(dagNode.outputValue(output.name, subName, variableSubstitution=False))
                vss = (list(), list())
                vss2 = (list(), list())
                if dagNode.outputRange(output.name, variableSubstitution=False):
                    vss = depends_variables.present(dagNode.outputRange(output.name, variableSubstitution=False)[0])
                    vss2 = depends_variables.present(dagNode.outputRange(output.name, variableSubstitution=False)[1])
                singleDollarList += vps[0] + vss[0] + vss2[0]
                doubleDollarList += vps[1] + vss[1] + vss2[1]
        return (list(set(singleDollarList)), list(set(doubleDollarList)))
Returns a tuple containing a list of all the single-dollar and a list 
dataset/ETHPy150Open andrew-gardner/dependsworkflow/depends/depends_main_window.py/MainWindow.dagNodeVariablesUsed