I have one module called foo.py
---------------------
class Foo:
foo = None
def get_foo():
return Foo.foo
if __name__ == "__main__":
import bar
Foo.foo = "foo"
bar.go()
---------------------
And another one called bar.py
---------------------
import foo
def go():
assert foo.get_foo() == "foo"
AFAICT you have 2 different "foo" modules here. The first foo is when
foo.py is called as a script, but it's not called "foo" it's called
"__main__" because it's called as a script. When "bar" is imported, it
imports "foo", but this is different. Technically this is the first time
you are *importing* foo. It's actually loaded a second time with the
name "foo".
A more simplified version of it is this:
$ cat foo.py
cat = 6
import bar
print '%s: %s.cat = %s' % (__file__, __name__, cat)
$ cat bar.py
import foo
foo.cat = 7
print '%s: %s.cat = %s' % (__file__, foo.__name__, foo.cat)
$ python foo.py
/home/marduk/test/foo.py: foo.cat = 6
/home/marduk/test/bar.py: foo.cat = 7
foo.py: __main__.cat = 6
OTOH:
$ python -c "import foo"
bar.py: foo.cat = 7
foo.py: foo.cat = 7
But, as others have said, this is confusing and should be avoided.
-a