def on_subscript(self, node):    # ('value', 'slice', 'ctx')
        val    = self.run(node.value)
        nslice = self.run(node.slice)
        ctx = node.ctx.__class__
        if ctx in ( ast.Load, ast.Store):
            if isinstance(node.slice, (ast.Index, ast.Slice, ast.Ellipsis)):
                return val.__getitem__(nslice)
            elif isinstance(node.slice, ast.ExtSlice):
                return val[(nslice)]
        else:
            msg = "subscript with unknown context"
            self.raise_exception(node, msg=msg)
Parses Adobe payloads, pulling out info useful to munki.
dataset/ETHPy150Open xraypy/xraylarch/lib/interpreter.py/Interpreter.on_subscript--crossover with--dataset/ETHPy150Open munki/munki/code/client/munkilib/adobeutils.py/getPayloadInfo