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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 _get_cfg_node(cfg, state):
 """ Get the CFGNode object on the control flow graph given an angr state. :param angr.analyses.CFGEmulated cfg: An instance of CFGEmulated. :param angr.SimState state: The current state. :return: A CFGNode instance if the node exists, or None if the node cannot be found. :rtype: CFGNode or None """


        call_stack_suffix = state.callstack.stack_suffix(cfg.context_sensitivity_level)
        is_syscall = state.history.jumpkind is not None and state.history.jumpkind.startswith('Ijk_Sys')

        block_id = cfg._generate_block_id(call_stack_suffix, state.addr, is_syscall)

        return cfg.get_node(block_id)