The keyword global
is only useful to change or create global variables in a local context, although creating global variables is seldom considered a good solution.
def bob(): me = "locally defined" # Defined only in local context print(me) bob() print(me) # Asking for a global variable
The above will give you:
locally defined Traceback (most recent call last): File "file.py", line 9, in <module> print(me) NameError: name 'me' is not defined
While if you use the global
statement, the variable will become available “outside” the scope of the function, effectively becoming a global variable.
def bob(): global me me = "locally defined" # Defined locally but declared as global print(me) bob() print(me) # Asking for a global variable
So the above code will give you:
locally defined locally defined
In addition, due to the nature of python, you could also use global
to declare functions, classes or other objects in a local context. Although I would advise against it since it causes nightmares if something goes wrong or needs debugging.