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This article mainly introduces the relevant knowledge of "how to use python variables in scope". The editor shows you the operation process through an actual case. The operation method is simple, fast and practical. I hope this article "how to use python variables in scope" can help you solve the problem.

1. When the global scope variable is not defined (assignment or parameter), the global scope variable can be read in the local scope.

> def func (): print (a) # is not a good way to write > a = 2 # an is a global scope variable, but can be read by local scope > func () 2

2. When a variable is defined as a local scope, the local scope no longer reads the variables in the global scope, and an error occurs when the variable is read before it is defined.

> b = 5 > def func (a): print (a) print (b) # error occurred while trying to print b variable, program termination b = 8 > func (3) 3Traceback (most recent call last): File ", line 1, in func (3) File", line 3, in func print (b) UnboundLocalError: local variable 'b'referenced before assignment on "how python variables are used in scope" ends here Thank you for your reading. If you want to know more about the industry, you can follow the industry information channel. The editor will update different knowledge points for you every day.

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