Global Variable from a different file Python

Question

So I have two different files somewhat like this   file1 py  from file2 import   foo    bar   test   SomeClass      file2 py  class SomeClass       def   init    self           global foo          print foo    However I cannot seem to get file2 to recognize variables from file1 even though its imported into file1 already  It would be extremely helpful if this is possible in some way

User · Answer

Just put your globals in the file you are importing

User · Answer

from file2 import   is making copies  You want to do this   import file2 print file2 foo print file2 SomeClass

User · Answer

When you write  from file2 import     it actually copies the names defined in file2 into the namespace of file1  So if you reassign those names in file1  by writing  foo    bar    for example  it will only make that change in file1  not file2  Note that if you were to change an attribute of foo  say by doing  foo blah    bar    then that change would be reflected in file2  because you are modifying the existing object referred to by the name foo  not replacing it with a new object   You can get the effect you want by doing this in file1 py   import file2 file2 foo    bar  test   SomeClass      note that you should delete from foo import    although I would suggest thinking carefully about whether you really need to do this  It s not very common that changing one module s variables from within another module is really justified

User · Answer

All given answers are wrong  It is impossible to globalise a variable inside a function in a separate file

User · Answer

After searching  I got this clue  https   instructobit com tutorial 108 How-to-share-global-variables-between-files-in-Python  the key is  turn on the function to call the variabel that set to global if a function activated   then import the variabel again from that file   i give you the hard example so you can understood   file chromy py  from selenium import webdriver from selenium webdriver chrome options import Options  def opennormal        global driver     options   Options       driver   webdriver Chrome chrome options options   def gotourl str       url   str     driver get url    file tester py  from chromy import    this command call all function in chromy py  but the  driver  variable in opennormal function is not exists yet  run  dir   to check what you call   opennormal    this command activate the driver variable to global  but remember  at the first import you not import it   then do this  this is the key to solve  from chromy import driver  run dir   to check what you call and compare with the first dir   result    because you already re-import the global that you need  you can use it now  url    https   www google com  gotourl url    That s the way you call the global variable that you set in a function  cheers don t forget to give credit

User · Answer

global is a bit of a misnomer in Python  module namespace would be more descriptive   The fully qualified name of foo is file1 foo and the global statement is best shunned as there are usually better ways to accomplish what you want to do   I can t tell what you want to do from your toy example

User · Answer

Importing file2 in file1 py makes the global  i e   module level  names bound in file2 available to following code in file1 -- the only such name is SomeClass   It does not do the reverse  names defined in file1 are not made available to code in file2 when file1 imports file2   This would be the case even if you imported the right way  import file2  as  nate correctly recommends  rather than in the horrible  horrible way you re doing it  if everybody under the Sun forgot the very existence of the construct from     import    life would be so much better for everybody    Apparently you want to make global names defined in file1 available to code in file2 and vice versa   This is known as a  cyclical dependency  and is a terrible idea  in Python  or anywhere else for that matter    So  rather than showing you the incredibly fragile  often unmaintainable hacks to achieve  some semblance of  a cyclical dependency in Python  I d much rather discuss the many excellent way in which you can avoid such terrible structure   For example  you could put global names that need to be available to both modules in a third module  e g  file3 py  to continue your naming streak -  and import that third module into each of the other two  import file3 in both file1 and file2  and then use file3 foo etc  that is  qualified names  for the purpose of accessing or setting those global names from either or both of the other modules  not barenames    Of course  more and more specific help could be offered if you clarified  by editing your Q  exactly why you think you need a cyclical dependency  just one easy prediction  no matter what makes you think you need a cyclical dependency  you re wrong -

[python] Global Variable from a different file Python

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