'Get the VariableManagerInternal object for a function or a region.
:param str or int key: Key of the region. "global" for the global region, or a function address for the
function.
:return:               The VariableManagerInternal object.
:rtype:                VariableManagerInternal'

def __getitem__(self, key):

    if (key == 'global'):
        return self.global_manager
    else:
        return self.get_function_manager(key)
