I have two python modules:
import b def hello(): print "hello" print "a.py" print hello() print b.hi()
import a def hi(): print "hi"
When I run
a.py, I get:
AttributeError: 'module' object has no attribute 'hi'
What does the error mean? How do I fix it?
You have mutual top-level imports, which is almost always a bad idea.
If you really must have mutual imports in Python, the way to do it is to import them within a function:
# In b.py: def cause_a_to_do_something(): import a a.do_something()
Now a.py can safely do
import b without causing problems.
(At first glance it might appear that
cause_a_to_do_something() would be hugely inefficient because it does an
import every time you call it, but in fact the import work only gets done the first time. The second and subsequent times you import a module, it's a quick operation.)
I have also seen this error when inadvertently naming a module with the same name as one of the standard Python modules. E.g. I had a module called
commands which is also a Python library module. This proved to be difficult to track down as it worked correctly on my local development environment but failed with the specified error when running on Google App Engine.