Undefined name: from functools import partial

flake8 testing of https://github.com/toandaominh1997/EfficientDet.Pytorch on Python 3.8.0

$ flake8 . --count --select=E9,F63,F7,F82 --show-source --statistics

./eval.py:81:32: F821 undefined name 'device'
            images = images.to(device)
                               ^
./eval.py:82:42: F821 undefined name 'device'
            annotations = annotations.to(device)
                                         ^
./utils/vis_bbox.py:107:26: F821 undefined name 'label_names'
            label_names= label_names
                         ^
./models/bifpn.py:91:17: F821 undefined name 'xavier_init'
                xavier_init(m, distribution='uniform')
                ^
./models/bifpn.py:167:17: F821 undefined name 'xavier_init'
                xavier_init(m, distribution='uniform')
                ^
./models/retinahead.py:8:13: F821 undefined name 'partial'
    pfunc = partial(func, **kwargs) if kwargs else func
            ^
6     F821 undefined name 'device'
6

https://flake8.pycqa.org/en/latest/user/error-codes.html

On the flake8 test selection, this PR does not focus on "style violations" (the majority of flake8 error codes that psf/black can autocorrect). Instead these tests are focus on runtime safety and correctness:

E9 tests are about Python syntax errors usually raised because flake8 can not build an Abstract Syntax Tree (AST). Often these issues are a sign of unused code or code that has not been ported to Python 3. These would be compile-time errors in a compiled language but in a dynamic language like Python they result in the script halting/crashing on the user.
F63 tests are usually about the confusion between identity and equality in Python. Use ==/!= to compare str, bytes, and int literals is the classic case. These are areas where a == b is True but a is b is False (or vice versa). Python >= 3.8 will raise SyntaxWarnings on these instances.
F7 tests logic errors and syntax errors in type hints
F82 tests are almost always undefined names which are usually a sign of a typo, missing imports, or code that has not been ported to Python 3. These also would be compile-time errors in a compiled language but in Python a NameError is raised which will halt/crash the script on the user.

toandaominh1997 / EfficientDet.Pytorch

Undefined name: from functools import partial #69