Static variables in Python that are shared across files

Question

I am pretty new to Python and I could\'t find a way to have static variables that are shared across different python files... In Java, it seems quite straight forward to do so..

Answer 1

The problem is that (I suppose) you are launching separately user1.py and user2.py. So static values of class Shared are not preserved across different invocations.

But that's otherwise a perfectly correct way of sharing data : you declare classes or even variable in one file that is imported in the others.

But Python is not Java, and everything does not need to be a class. You could do :

• data.py

  list_vars = []
  var = ""
  
  def print_vars():
      print "list_vars = " + str(Shared.list_vars)
      print "var = " + Shared.var
  

• user1.py

  import time
  import data as shared
  
  shared.list_vars.append("001")
  time.sleep(5.0)
  shared.print_vars()
  
  # It prints:
  # list_vars = ['001']
  # var =
  

• user2.py

  import time
  import data as shared
  
  shared.var = "002"
  time.sleep(5.0)
  shared.print_vars()
  
  # It prints:
  # list_vars = []
  # var = 002
  

• main.py

  import user1
  # It prints:
  # list_vars = ['001']
  # var =
  import user2
  # It prints:
  # list_vars = ['001']
  # var = 002