Python: How do I pass variables between class instances or get the caller?

Question

class foo():
  def __init__(self)
    self.var1 = 1

class bar():
  def __init__(self):
    print \"foo var1\"

f = foo()
b = bar()

In foo, I am do

Answer 1

Perhaps this was added to the language since this question was asked...

The global keyword will help.

x = 5

class Foo():
    def foo_func(self):
        global x    # try commenting this out.  that would mean foo_func()
                    # is creating its own x variable and assigning it a
                    # value of 3 instead of changing the value of global x
        x = 3

class Bar():
    def bar_func(self):
        print(x)

def run():
    bar = Bar()     # create instance of Bar and call its
    bar.bar_func()  # function that will print the current value of x

    foo = Foo()     # init Foo class and call its function
    foo.foo_func()  # which will add 3 to the global x variable

    bar.bar_func()  # call Bar's function again confirming the global
                    # x variable was changed 


if __name__ == '__main__':
    run()