plot test: dropped python2 imports
I copied them from test_command_line.py but they are misleading
because cantools uses format strings which require python3 (e.g. database/can/formats/arxml.py, line 25).
Therefore the tests cannot pass in python2.
import os
import unittest
-
-try:
from unittest import mock
-except ImportError:
- import mock
-
-try:
- from StringIO import StringIO
-except ImportError:
from io import StringIO
-
import cantools
import matplotlib.pyplot
