You need to use the global keyword in a function if you use the global variable in a way that would otherwise be interpreted as an assignment to ... ... <看更多>

[core] modifications to global variable has no effect #15946 ... File "HOME/.local/lib/python3.8/site-packages/ray/tune/function_runner.py", ... ... <看更多>

The variable is global because any Python function or class defined in this module or notebook, is able to access this variable. For example:. ... <看更多>

Performance is irrelevant. Globals are evil (as gnat mentioned); you are best off forgetting the global keyword exists. There is always a better way. ... <看更多>