Evan Hicks
—The exception UnboundLocalError: local variable 'index' referenced before assignment
happens in Python when you use a global variable in a function that also defines a local version of the same variable.
index = 0 def foo(): if index == 0: print("ZERO") index = 1 foo()
Because index is defined globally as well as inside the foo()
function, Python throws an exception if you try to use the variable inside foo
before it’s declared.
In this case, we want to rename the variable to avoid the conflict.
index = 0 def foo(): if index == 0: print("ZERO") findex = 1 foo()
If you’re looking to get a deeper understanding of how Python application monitoring works, take a look at the following articles:
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