How do I fix PyDev "Undefined variable from import" errors?

The post marked as answer gives a workaround, not a solution.

This solution works for me:

• Go to Window - Preferences - PyDev - Interpreters - Python Interpreter
• Go to the Forced builtins tab
• Click on New...
• Type the name of the module (multiprocessing in my case) and click OK

Not only will the error messages disappear, the module members will also be recognized.

I'm using opencv which relies on binaries etc so I have scripts where every other line has this silly error. Python is a dynamic language so such occasions shouldn't be considered errors.

I removed these errors altogether by going to:

Window -> Preferences -> PyDev -> Editor -> Code Analysis -> Undefined -> Undefined Variable From Import -> Ignore

And that's that.

It may also be, Window -> Preferences -> PyDev -> Editor -> Code Analysis -> Imports -> Import not found -> Ignore

For code in your project, the only way is adding a declaration saying that you expected that -- possibly protected by an if False so that it doesn't execute (the static code-analysis only sees what you see, not runtime info -- if you opened that module yourself, you'd have no indication that main was expected).

To overcome this there are some choices:

1. If it is some external module, it's possible to add it to the forced builtins so that PyDev spawns a shell for it to obtain runtime information (see http://pydev.org/manual_101_interpreter.html for details) -- i.e.: mostly, PyDev will import the module in a shell and do a dir(module) and dir on the classes found in the module to present completions and make code analysis.

2. You can use Ctrl+1 (Cmd+1 for Mac) in a line with an error and PyDev will present you an option to add a comment to ignore that error.

3. It's possible to create a stub module and add it to the predefined completions (http://pydev.org/manual_101_interpreter.html also has details on that).