It appears white wavy line edit mode because the code does not meet specifications Python.
As shown below:
The correct approach should be to the "=" on both sides by a space, "" followed by a space followed, as well as comment # to write a comment box content and so on.
But always gave me a sense of red tape.
You can see the bottom right corner pycharm of a man-shaped symbol,
Click on this symbol, you can see three options
The first is off spec check and grammar check codes, the second is only spec check closing code, the code is a last spec check and grammar check are open.
We recommend the use of a second, so it will only remove the white wavy lines, and when a syntax error, there are still reminders red wavy line.