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Global python variable




I have two packages:




In the script implemented in Unloader.py, the function is called, which is located in GetRequest.py. In addition, a global variable is declared in Unloader.py, which is used in the above function from GetRequest.py. But for some reason this global variable turns out to be invisible:

NameError: global name 'countFailResponse' is not defined

Here’s an example


global countNullResponse
response, isGetData = GetRequests.Request (query)


def Request (query):
  global countNullResponse
  countNullResponse + = 1

How can I fix the code so that Request sees the global variable countNullResponse ?

Answer 1

The global keyword is designed to refer to a module’s global variable, rather than creating a local variable in a function of the same name.

Suppose we have a countNullResponse variable in our module. If we try to write countNullResponse + = 1 inside any function, then we get an error like NameError , because Python will look for this variable in the local namespace, that is, in the namespace functions. To refer to a global variable and the global keyword was created:

countNullResponse = 0
def Request (query):
  global countNullResponse
  countNullResponse + = 1
  return countNullResponse, True
response, isGetData = Request ('some url')
print (response, isGetData)

If you want to receive countNullResponse , but do not want to store everything in one module, then I suggest you move this variable to another module.

That is, your GetResponse might look like this:

countNullResponse = 0
def Request (query):
  global countNullResponse
  result = Connect (query)
  countNullResponse + = 1
  return countNullResponse, result

And the Unlodaer module is like this:

from GetResponse import *
response, isGetData = Request (query)

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