Windows Defender might be impacting your build performance

After I updated my PyCharm IDE to 19.2.0 from the 19.1.2. I am getting the following warning:

"Windows Defender might be impacting your build performance. PyCharm checked 
thefollowing directories:
C:\Workspace\Projects\576_UniversityTwitter 
C:\Users\Burak\.PyCharmCE2019.2\system 
C:\Users\Burak\.gradle

Do you think that it is secure, necessary and really improve the performance?

You need to exclude those directories in your Windows Security's Exclusion list.

1. Type Windows Security in your windows Search bar
2. Click Virus & threat protection
3. Under Virus & threat protection settings header, click Manage Settings
4. Under Exclusions header, click Add or remove exclusions
5. Click Add an exclusion
6. Select type Folder
7. Enter the directory
8. You are done

Yes it is secure, necessary and really improves the performance as the real-time scanning is enabled in Windows defender by default. Read this: Minimize the impact of antivirus software on build speed.