text: Title: Matplotlib version (>=3.0.0) backends don't support Yellowbrick
  Body: **Describe the issue**
  A clear and concise description of what the issue is.
  
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  @DistrictDataLabs/team-oz-maintainers
  The error says YellowBrick  0.9 has requirement matplotlib <3.0 and >=1.5.1.So,the version of matplotlib without updating works fine.I will recommend users not to update matplotlib as its version 3.0.2's backends don't support yellowbrick.