pylint: global-variable-not-assigned

Putnik :

The code:

assets = {}                # line 1

def myfunc():
    global assets          # line 4

    if assets.get("a", None) is None:
        assets["a"] = 2

The pylint result:

C:  1, 0: Invalid constant name "assets" (invalid-name)
C:  4, 4: Invalid constant name "assets" (invalid-name)
W:  4, 4: Using global for 'assets' but \
    no assignment is done (global-variable-not-assigned)

The function will be called later more than once so I just want to assign (in real life some time-consuming process) the value only once.

How should I do it properly?

p.s.: Thanks @deceze, I was confused by the fact that if instead of assets = {} I use assets = {"a":2} the behavior will be absolutely different.

deceze :

The linter tells you that you're not assigning to assets, meaning assets = .... Which means you do not need global assets. The variable assets from the outer scope will be available inside myfunc anyway for reading. You only need global if you want to assign a different value to the variable in the outer scope. assets['a'] = 2 is not assigning a different value to it, it's just mutating the existing value.

So, remove the global assets line.